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Graph theory

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4060:. In these applications, graphs are ordered by specificity, meaning that more constrained graphs—which are more specific and thus contain a greater amount of information—are subsumed by those that are more general. Operations between graphs include evaluating the direction of a subsumption relationship between two graphs, if any, and computing graph unification. The unification of two argument graphs is defined as the most general graph (or the computation thereof) that is consistent with (i.e. contains all of the information in) the inputs, if such a graph exists; efficient unification algorithms are known. 3006: 519: 544: 532: 42: 6832: 142: 1535: 3327:, are used to represent structures in which pairwise connections have some numerical values. For example, if a graph represents a road network, the weights could represent the length of each road. There may be several weights associated with each edge, including distance (as in the previous example), travel time, or monetary cost. Such weighted graphs are commonly used to program GPS's, and travel-planning search engines that compare flight times and costs. 3224: 7870: 6844: 7880: 7890: 6868: 6856: 4199:
Decomposition, defined as partitioning the edge set of a graph (with as many vertices as necessary accompanying the edges of each part of the partition), has a wide variety of questions. Often, the problem is to decompose a graph into subgraphs isomorphic to a fixed graph; for instance, decomposing a
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A graph drawing should not be confused with the graph itself (the abstract, non-visual structure) as there are several ways to structure the graph drawing. All that matters is which vertices are connected to which others by how many edges and not the exact layout. In practice, it is often difficult
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A graph is an abstraction of relationships that emerge in nature; hence, it cannot be coupled to a certain representation. The way it is represented depends on the degree of convenience such representation provides for a certain application. The most common representations are the visual, in which,
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makes fundamental use of the notion of "discharging" developed by Heesch. The proof involved checking the properties of 1,936 configurations by computer, and was not fully accepted at the time due to its complexity. A simpler proof considering only 633 configurations was given twenty years later by
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and conservation efforts where a vertex can represent regions where certain species exist (or inhabit) and the edges represent migration paths or movement between the regions. This information is important when looking at breeding patterns or tracking the spread of disease, parasites or how changes
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as a means to model molecules. Graphs and networks are excellent models to study and understand phase transitions and critical phenomena. Removal of nodes or edges leads to a critical transition where the network breaks into small clusters which is studied as a phase transition. This breakdown is
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software. Under the umbrella of social networks are many different types of graphs. Acquaintanceship and friendship graphs describe whether people know each other. Influence graphs model whether certain people can influence the behavior of others. Finally, collaboration graphs model whether two
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Graphs are usually represented visually by drawing a point or circle for every vertex, and drawing a line between two vertices if they are connected by an edge. If the graph is directed, the direction is indicated by drawing an arrow. If the graph is weighted, the weight is added on the arrow.
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Many problems and theorems in graph theory have to do with various ways of coloring graphs. Typically, one is interested in coloring a graph so that no two adjacent vertices have the same color, or with other similar restrictions. One may also consider coloring edges (possibly so that no two
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graphs can be used to represent functional connections between brain areas that interact to give rise to various cognitive processes, where the vertices represent different areas of the brain and the edges represent the connections between those areas. Graph theory plays an important role in
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in a given graph. Again, some important graph properties are hereditary with respect to induced subgraphs, which means that a graph has a property if and only if all induced subgraphs also have it. Finding maximal induced subgraphs of a certain kind is also often NP-complete. For example:
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structures on the other hand provide faster access for some applications but can consume huge amounts of memory. Implementations of sparse matrix structures that are efficient on modern parallel computer architectures are an object of current investigation.
3336: 3469:, published in 1969, was "considered the world over to be the definitive textbook on the subject", and enabled mathematicians, chemists, electrical engineers and social scientists to talk to each other. Harary donated all of the royalties to fund the 3858:
or subcontraction of a graph is any graph obtained by taking a subgraph and contracting some (or no) edges. Many graph properties are hereditary for minors, which means that a graph has a property if and only if all minors have it too. For example,
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and study the relationships between them, such as metabolic pathways and gene regulatory networks. Evolutionary trees, ecological networks, and hierarchical clustering of gene expression patterns are also represented as graph structures.
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Graphs can be used to model many types of relations and processes in physical, biological, social and information systems. Many practical problems can be represented by graphs. Emphasizing their application to real-world systems, the term
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in 1959. Cayley linked his results on trees with contemporary studies of chemical composition. The fusion of ideas from mathematics with those from chemistry began what has become part of the standard terminology of graph theory.
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electrical modeling of electrical networks, here, weights are associated with resistance of the wire segments to obtain electrical properties of network structures. Graphs are also used to represent the micro-scale channels of
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English edition, Wiley 1961; Methuen & Co, New York 1962; Russian, Moscow 1961; Spanish, Mexico 1962; Roumanian, Bucharest 1969; Chinese, Shanghai 1963; Second printing of the 1962 first English edition, Dover, New York
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from one page to another. A similar approach can be taken to problems in social media, travel, biology, computer chip design, mapping the progression of neuro-degenerative diseases, and many other fields. The development of
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used for manipulating the graph. Theoretically one can distinguish between list and matrix structures but in concrete applications the best structure is often a combination of both. List structures are often preferred for
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and non-causal linked structures are graphs that are used to represent networks of communication, data organization, computational devices, the flow of computation, etc. For instance, the link structure of a
3480:: "Is it true that any map drawn in the plane may have its regions colored with four colors, in such a way that any two regions having a common border have different colors?" This problem was first posed by 3018:
is sometimes defined to mean a graph in which attributes (e.g. names) are associated with the vertices and edges, and the subject that expresses and understands real-world systems as a network is called
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complete graph into Hamiltonian cycles. Other problems specify a family of graphs into which a given graph should be decomposed, for instance, a family of cycles, or decomposing a complete graph
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and its various generalizations. The crossing number of a graph is the minimum number of intersections between edges that a drawing of the graph in the plane must contain. For a
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usually, vertices are drawn and connected by edges, and the tabular, in which rows of a table provide information about the relationships between the vertices within the graph.
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for subgraphs, which means that a graph has the property if and only if all subgraphs have it too. Unfortunately, finding maximal subgraphs of a certain kind is often an
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are usually taken to be finite, and many of the well-known results are not true (or are rather different) for infinite graphs because many of the arguments fail in the
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in a form in close contact with the experimental numbers one wants to understand." In chemistry a graph makes a natural model for a molecule, where vertices represent
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The network graph formed by Knowledge (XXG) editors (edges) contributing to different Knowledge (XXG) language versions (vertices) during one month in summer 2013.
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Shah, Preya; Ashourvan, Arian; Mikhail, Fadi; Pines, Adam; Kini, Lohith; Oechsel, Kelly; Das, Sandhitsu R; Stein, Joel M; Shinohara, Russell T (2019-07-01).
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Vecchio, F (2017). ""Small World" architecture in brain connectivity and hippocampal volume in Alzheimer's disease: a study via graph theory from EEG data".
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Shah, Preya; Ashourvan, Arian; Mikhail, Fadi; Pines, Adam; Kini, Lohith; Oechsel, Kelly; Das, Sandhitsu R; Stein, Joel M; Shinohara, Russell T (2019-07-01).
4023: 3193:, graphs can represent local connections between interacting parts of a system, as well as the dynamics of a physical process on such systems. Similarly, in 3661:
was very influential on the subject of graph drawing. Among other achievements, he introduced the use of linear algebraic methods to obtain graph drawings.
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to decide if two drawings represent the same graph. Depending on the problem domain some layouts may be better suited and easier to understand than others.
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to model and analyse datasets with complex relationships. For example, graph-based methods are often used to 'cluster' cells together into cell-types in
3137:) are common in the analysis of language as a graph. Indeed, the usefulness of this area of mathematics to linguistics has borne organizations such as 2504: 4328: 2449:
is an edge that joins a vertex to itself. Directed graphs as defined in the two definitions above cannot have loops, because a loop joining a vertex
4607: 3830:. It asks whether two graphs are isomorphic. It is not known whether this problem is NP-complete, nor whether it can be solved in polynomial time. 691: 238: 4009:
coincident edges are the same color), or other variations. Among the famous results and conjectures concerning graph coloring are the following:
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The tabular representation lends itself well to computational applications. There are different ways to store graphs in a computer system. The
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is an edge that joins a vertex to itself. Graphs as defined in the two definitions above cannot have loops, because a loop joining a vertex
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Kumar, Ankush; Kulkarni, G. U. (2016-01-04). "Evaluating conducting network based transparent electrodes from geometrical considerations".
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with particular properties. Enumerative graph theory then arose from the results of Cayley and the fundamental results published by
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Another class of problems has to do with the extent to which various species and generalizations of graphs are determined by their
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of a graph is any graph obtained by subdividing some (or no) edges. Subdivision containment is related to graph properties such as
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and published in 1736 is regarded as the first paper in the history of graph theory. This paper, as well as the one written by
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Mathematical results on scale-free random graphs in "Handbook of Graphs and Networks" (S. Bornholdt and H.G. Schuster (eds))
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came from the use of the techniques of modern algebra. The first example of such a use comes from the work of the physicist
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Many problems involve characterizing the members of various classes of graphs. Some examples of such questions are below:
4064: 3370:. Euler's formula relating the number of edges, vertices, and faces of a convex polyhedron was studied and generalized by 3098: 4562: 4557: 1045: 963: 7795: 7383: 7291: 7196: 6972: 6957: 6172: 4845: 4830: 4299: 4178: 4018: 3965: 3905: 3795: 3567: 3559: 63: 5780: 5552: 4567: 3786:: the problem of counting graphs meeting specified conditions. Some of this work is found in Harary and Palmer (1973). 3005: 7883: 7618: 7116: 6775: 6331: 6157: 5425: 4693: 4587: 4365: 4323: 3295:; nervous systems can be seen as a graph, where the nodes are neurons and the edges are the connections between them. 518: 6186: 4552: 4527: 3594: 1538:
A directed graph with three vertices and four directed edges (the double arrow represents an edge in each direction).
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Still another such problem, the minor containment problem, is to find a fixed graph as a minor of a given graph. A
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can be represented by a directed graph, in which the vertices represent web pages and directed edges represent
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Definitions in graph theory vary. The following are some of the more basic ways of defining graphs and related
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The original set cover problem, also called hitting set, can be described as a vertex cover in a hypergraph.
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The autonomous development of topology from 1860 and 1930 fertilized graph theory back through the works of
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A graph structure can be extended by assigning a weight to each edge of the graph. Graphs with weights, or
2179:, not allowed under the definition above, are two or more edges with both the same tail and the same head. 7850: 7681: 7562: 7329: 7319: 7314: 6788: 6685: 6665: 6660: 6589: 6314: 5615: 4634: 4629: 4582: 4500: 4465: 4425: 4405: 4345: 3754: 3676: 3497: 3489: 3428: 3308: 3110: 3078: 543: 531: 130: 41: 32: 5426:"graphsim: An R package for simulating gene expression data from graph structures of biological pathways" 4800: 4132:
There are numerous problems arising especially from applications that have to do with various notions of
3672:, the crossing number is zero by definition. Drawings on surfaces other than the plane are also studied. 8023: 7820: 7790: 7780: 7676: 7590: 7466: 7406: 7373: 7363: 7246: 7211: 7201: 7138: 7007: 6982: 6977: 6942: 6815: 6745: 6622: 6546: 6485: 6470: 6465: 6442: 6324: 5609: 5243:
Vecchio, F (2013). "Brain network connectivity assessed using graph theory in frontotemporal dementia".
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to itself is the edge (for an undirected simple graph) or is incident on (for an undirected multigraph)
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published a method for solving the problem using computers. A computer-aided proof produced in 1976 by
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to the product of in- or co-variants whose separate graphs are given. " (italics as in the original).
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This article is about sets of vertices connected by edges. For graphs of mathematical functions, see
2592:. So to allow loops the definitions must be expanded. For directed simple graphs, the definition of 1534: 940:. To allow loops, the definitions must be expanded. For undirected simple graphs, the definition of 111:, where edges link two vertices asymmetrically. Graphs are one of the principal objects of study in 7845: 7770: 7686: 7671: 7436: 7216: 7173: 7168: 7065: 7055: 7027: 6810: 6720: 6642: 6541: 6475: 6432: 6422: 6402: 4617: 4602: 4572: 4450: 4252: 3860: 3811: 3737:, a matrix of 0's and 1's whose rows represent vertices and whose columns represent edges, and the 3513: 3403: 3190: 2445: 2189: 825: 798: 568: 28: 6219: 6152: 6125: 5916: 4715: 3315:. Algebraic graph theory has been applied to many areas including dynamic systems and complexity. 2469:
to itself is the edge (for a directed simple graph) or is incident on (for a directed multigraph)
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Heinrich Heesch: Untersuchungen zum Vierfarbenproblem. Mannheim: Bibliographisches Institut 1969.
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of the asymptotic probability of graph connectivity, gave rise to yet another branch, known as
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of a vertex is the number of edges that are incident to it, where a loop is counted twice. The
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and compositional semantics follow tree-based structures, whose expressive power lies in the
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Phase Transitions in Combinatorial Optimization Problems, Section 3: Introduction to Graphs
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Appel, K.; Haken, W. (1977), "Every planar map is four colorable. Part II. Reducibility",
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Ascertaining relationships among classes (e.g. does one property of graphs imply another)
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There are other techniques to visualize a graph away from vertices and edges, including
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used to model pairwise relations between objects. A graph in this context is made up of
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Robertson, N.; Sanders, D.; Seymour, P.; Thomas, R. (1997), "The four color theorem",
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A similar problem, the subdivision containment problem, is to find a fixed graph as a
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The introduction of probabilistic methods in graph theory, especially in the study of
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diagram or chemicograph. I give a rule for the geometrical multiplication of graphs,
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Fractal Music, Hypercards, and more…Mathematical Recreations from Scientific American
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led to the study of the colorings of the graphs embedded on surfaces with arbitrary
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the same year. Many incorrect proofs have been proposed, including those by Cayley,
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In mathematics, graphs are useful in geometry and certain parts of topology such as
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is a modified form of the adjacency matrix that incorporates information about the
3711: 3669: 3622: 3493: 3466: 3312: 3292: 2429: 1762: 154: 6201: 5177: 3335: 509:. A vertex may exist in a graph and not belong to an edge. Under this definition, 6223: 6181: 5946: 5628: 5256: 5036: 2585:{\displaystyle \left\{(x,y)\mid (x,y)\in V^{2}\;{\textrm {and}}\;x\neq y\right\}} 8002: 7815: 7441: 7353: 6715: 6379: 6302: 6207: 5723: 5158:"A social network analysis of Twitter: Mapping the digital humanities community" 5005:
Mashaghi, A.; et al. (2004). "Investigation of a protein complex network".
4860: 4671: 3658: 3528:. The works of Ramsey on colorations and more specially the results obtained by 3304: 3090: 3036: 1121: 54: 5134: 5117: 17: 7835: 7765: 7358: 7091: 6947: 6700: 6579: 6374: 5453: 5213: 4688: 4460: 4239:, a decomposition into a collection of cycles covering each edge exactly twice 4230: 4056:
Constraint modeling theories concern families of directed graphs related by a
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in a given graph. One reason to be interested in such a question is that many
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people work together in a particular way, such as acting in a movie together.
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Graph-theoretic methods, in various forms, have proven particularly useful in
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is the special case of set cover problem where sets to cover are every edges.
767:{\displaystyle \phi :E\to \{\{x,y\}\mid x,y\in V\;{\textrm {and}}\;x\neq y\}} 308:{\displaystyle E\subseteq \{\{x,y\}\mid x,y\in V\;{\textrm {and}}\;x\neq y\}} 7949: 7340: 7301: 5789: 4973: 4735: 4705: 4288: 3723: 3706: 3408: 3239: 3231: 3158: 3050: 3045: 5900: 5537: 5511: 5264: 5221: 5101: 5075: 4177:
problem is the special case of set cover problem where sets are the closed
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The four color problem remained unsolved for more than a century. In 1969
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to handle graphs is therefore of major interest in computer science. The
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Graph drawing also can be said to encompass problems that deal with the
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of vertices (that is, an edge is associated with two distinct vertices).
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of vertices (that is, an edge is associated with two distinct vertices).
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of vertices (that is, an edge is associated with two distinct vertices).
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Example of simple undirected graph with 3 vertices, 3 edges and 4 loops.
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of vertices (that is, an edge is associated with two distinct vertices).
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Cauchy, A. L. (1813), "Recherche sur les polyèdres - premier mémoire",
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One of the most famous and stimulating problems in graph theory is the
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Some specific decomposition problems that have been studied include:
3585:. Another important factor of common development of graph theory and 3378:, and represents the beginning of the branch of mathematics known as 3094: 5652: 4946:
Hale, Scott A. (2014). "Multilinguals and Knowledge (XXG) editing".
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systems focusing on rule-based in-memory manipulation of graphs are
2105:. A vertex may exist in a graph and not belong to an edge. The edge 6884: 5585:
L'Huillier, S.-A.-J. (1812–1813), "Mémoire sur la polyèdrométrie",
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was led by an interest in particular analytical forms arising from
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To avoid ambiguity, this type of object may be called precisely an
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For vertices U,V,W and X, the degrees are 2,2,3 and 1 respectively.
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To avoid ambiguity, this type of object may be called precisely an
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Graph Theory with Applications to Engineering and Computer Science
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To avoid ambiguity, this type of object may be called precisely a
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To avoid ambiguity, this type of object may be called precisely a
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Concise, annotated list of graph theory resources for researchers
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In one more general sense of the term allowing multiple edges, a
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In one more general sense of the term allowing multiple edges, a
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Lists, Decisions and Graphs. With an Introduction to Probability
3178: 7908: 6888: 6274: 6210:— non-technical paper discussing graphs of people and computers 3626:, which has been a fruitful source of graph-theoretic results. 3441:" Every invariant and co-variant thus becomes expressible by a 3516:. Tait's reformulation generated a new class of problems, the 537:
For vertices A,B,C and D, the degrees are respectively 4,4,5,1
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in 1941 was at the origin of another branch of graph theory,
3138: 3753:
of the vertices, and is useful in some calculations such as
3385:
More than one century after Euler's paper on the bridges of
5118:"Applications of Graph Theory [Scanning the Issue]" 1110:. To avoid ambiguity, these types of objects may be called 6243:
with references and links to graph library implementations
1291:
of a graph is the maximum of the degrees of its vertices.
5823:"Every planar map is four colorable. Part I. Discharging" 1331:
The edges of an undirected simple graph permitting loops
3484:
in 1852 and its first written record is in a letter of
1553:
In one restricted but very common sense of the term, a
149:
In one restricted but very common sense of the term, a
5385:. Redesigned network strictly based on Moreno (1934), 3133:) and morphology (e.g. finite-state morphology, using 2813:
The edges of a directed simple graph permitting loops
4948:
Proceedings of the 2014 ACM conference on Web science
2983: 2963: 2939: 2919: 2887: 2867: 2843: 2819: 2717: 2697: 2618: 2598: 2507: 2475: 2455: 2327: 2277: 2239: 2192: 2147: 2111: 2091: 2071: 2047: 2027: 2000: 1976: 1952: 1932: 1912: 1892: 1860: 1837: 1814: 1779: 1642: 1604: 1563: 1500: 1476: 1456: 1424: 1404: 1380: 1360: 1337: 1255: 1221: 1197: 1177: 1153: 1133: 1048: 1028: 966: 946: 872: 828: 808: 694: 656: 618: 571: 495: 475: 451: 431: 404: 384: 352: 241: 203: 162: 5610:"On the theory of the analytical forms called trees" 4216:
specified trees having, respectively, 1, 2, 3, ...,
3818:
Finding the largest complete subgraph is called the
7988: 7940: 7753: 7700: 7662: 7609: 7571: 7533: 7475: 7392: 7338: 7300: 7245: 7182: 7115: 7079: 7036: 7000: 6933: 6774: 6731: 6641: 6603: 6570: 6522: 6494: 6441: 6388: 6345: 3407:. This study had many implications for theoretical 1103:{\displaystyle \phi :E\to \{\{x,y\}\mid x,y\in V\}} 1015:{\displaystyle E\subseteq \{\{x,y\}\mid x,y\in V\}} 107:, where edges link two vertices symmetrically, and 6127:Graph Algorithms in The Language of Linear Algebra 6005: 5918:Graph Algorithms in the Language of Linear Algebra 5608: 5287: 5116: 3948:Another problem in subdivision containment is the 3461:The first textbook on graph theory was written by 3427:In particular, the term "graph" was introduced by 2989: 2969: 2945: 2925: 2905: 2873: 2849: 2825: 2788: 2703: 2683: 2604: 2584: 2493: 2461: 2416: 2283: 2245: 2222: 2165: 2129: 2097: 2077: 2053: 2033: 2006: 1982: 1958: 1938: 1918: 1898: 1878: 1843: 1823: 1792: 1725: 1610: 1587: 1512: 1482: 1462: 1442: 1410: 1386: 1366: 1343: 1271: 1237: 1203: 1183: 1159: 1139: 1102: 1034: 1014: 952: 932: 858: 814: 766: 662: 624: 601: 501: 481: 457: 437: 410: 390: 370: 307: 209: 186: 4233:, a decomposition into as few forests as possible 3842:Finding the largest edgeless induced subgraph or 3705:used depends on both the graph structure and the 3419:between 1935 and 1937. These were generalized by 3283:. Another use is to model genes or proteins in a 4933: 4909: 4884: 4613:Tarjan's strongly connected components algorithm 3826:One special case of subgraph isomorphism is the 3157:Graph theory is also used to study molecules in 1022:. For undirected multigraphs, the definition of 6182:A searchable database of small connected graphs 5945:Bender, Edward A.; Williamson, S. Gill (2010). 5777:Society for Industrial and Applied Mathematics 5657:Berichte der Deutschen Chemischen Gesellschaft 2691:. For directed multigraphs, the definition of 7920: 6924:Note: This template roughly follows the 2012 6900: 6286: 4063:For constraint frameworks which are strictly 3141:, as well as various 'Net' projects, such as 1550:is a graph in which edges have orientations. 8: 6262:2007 by Jorgen Bang-Jensen and Gregory Gutin 6260:Digraphs: Theory Algorithms and Applications 3924:if it contains as a subdivision neither the 3411:. The techniques he used mainly concern the 1851:elements that are not necessarily distinct. 1097: 1076: 1064: 1061: 1009: 988: 976: 973: 927: 888: 876: 873: 853: 847: 841: 829: 761: 722: 710: 707: 365: 353: 302: 263: 251: 248: 145:A graph with three vertices and three edges. 6073:Algorithmic Graph Theory and Perfect Graphs 5782:Looking Back, Looking Ahead: A SIAM History 4097:(also called the "Chinese postman problem") 3401:to study a particular class of graphs, the 3105:model the syntax of natural language using 555:Examples of finding the degree of vertices. 7927: 7913: 7905: 6907: 6893: 6885: 6293: 6279: 6271: 5732:, Cambridge University Press, p. 30, 5115:Adali, Tulay; Ortega, Antonio (May 2018). 3714:as they have smaller memory requirements. 3268:to the movement can affect other species. 3125:. Still, other methods in phonology (e.g. 2567: 2559: 2399: 2391: 1708: 1700: 917: 909: 751: 743: 292: 284: 6102:Mahadev, N. V. R.; Peled, Uri N. (1995). 6088:. Reading, Massachusetts: Addison-Wesley. 5967:Biggs, N.; Lloyd, E.; Wilson, R. (1986). 5899: 5888:Journal of Combinatorial Theory, Series B 5870: 5841: 5707: 5551:Biggs, N.; Lloyd, E.; Wilson, R. (1986), 5527: 5462: 5452: 5401:Discrete mathematics and its applications 5357:. Oxford University Press. Archived from 5176: 5091: 5018: 4955: 4329:List of unsolved problems in graph theory 3726:, an array of pairs of vertices, and the 3465:, and published in 1936. Another book by 3393:was introducing the concept of topology, 2982: 2962: 2938: 2918: 2886: 2866: 2842: 2818: 2775: 2716: 2696: 2670: 2617: 2597: 2561: 2560: 2553: 2506: 2474: 2454: 2393: 2392: 2385: 2326: 2276: 2238: 2191: 2146: 2110: 2090: 2070: 2046: 2026: 1999: 1975: 1951: 1931: 1911: 1891: 1859: 1836: 1813: 1784: 1778: 1702: 1701: 1694: 1641: 1603: 1562: 1499: 1475: 1455: 1423: 1403: 1379: 1359: 1336: 1264: 1256: 1254: 1230: 1222: 1220: 1196: 1176: 1152: 1132: 1047: 1027: 965: 945: 911: 910: 871: 827: 807: 745: 744: 693: 655: 617: 570: 494: 474: 450: 430: 403: 383: 351: 286: 285: 240: 202: 161: 6093:Harary, Frank; Palmer, Edgar M. (1973). 6036:. Englewood, New Jersey: Prentice-Hall. 5765:, W. H. Freeman and Company, p. 203 5424:Kelly, S.; Black, Michael (2020-07-09). 3790:Subgraphs, induced subgraphs, and minors 1533: 1112:undirected simple graph permitting loops 517: 140: 40: 6216:— tools to teach and learn graph theory 5995:Bollobás, Béla; Riordan, O. M. (2003). 5958:Théorie des graphes et ses applications 5403:(7th ed.). New York: McGraw-Hill. 4921:See, for instance, Graham et al., p. 5. 4896:See, for instance, Iyanaga and Kawada, 4877: 4259:into regular subgraphs of given degrees 3171:Feynman graphs and rules of calculation 3057:is often formalized and represented by 1298:, the maximum degree of each vertex is 1294:In an undirected simple graph of order 49:of a graph with 6 vertices and 7 edges. 7624:Knowledge representation and reasoning 6124:Kepner, Jeremy; Gilbert, John (2011). 5976:Bondy, J. A.; Murty, U. S. R. (2008). 5915:Kepner, Jeremy; Gilbert, John (2011). 5294:. New York: McGraw-Hill. p. viii. 3871:if it contains as a minor neither the 3745:indicates the degree of vertices. The 2798:directed simple graph permitting loops 1191:is often assumed to be non-empty, but 1116:undirected multigraph permitting loops 7649:Philosophy of artificial intelligence 6097:. New York, New York: Academic Press. 5286:Bjorken, J. D.; Drell, S. D. (1965). 1305:and the maximum size of the graph is 7: 6968:Energy consumption (Green computing) 6855: 6130:. Philadelphia, Pennsylvania: SIAM. 5999:(1st ed.). Weinheim: Wiley VCH. 3263:Likewise, graph theory is useful in 3238:Graph theory is also widely used in 3103:head-driven phrase structure grammar 2802:directed multigraph permitting loops 1211:is allowed to be the empty set. The 7654:Distributed artificial intelligence 6926:ACM Computing Classification System 6867: 6104:Threshold Graphs and Related Topics 4608:Push–relabel maximum flow algorithm 4278:Characterizing a class in terms of 4073:elaboration of linguistic structure 7159:Integrated development environment 5779:(2002), "The George Polya Prize", 4170:on subsets of vertices/subgraphs. 4045:Hadwiger conjecture (graph theory) 3683:, and other visualizations of the 3281:single-cell transcriptome analysis 1773:. In set theory and graph theory, 25: 7634:Automated planning and scheduling 7164:Software configuration management 6266:Graph Theory, by Reinhard Diestel 3271:Graphs are also commonly used in 2957:to one another, which is denoted 2018:of the edge. The edge is said to 1494:to one another, which is denoted 422:of the edge. The edge is said to 103:). A distinction is made between 7970:Microsoft Automatic Graph Layout 7888: 7878: 7869: 7868: 6866: 6854: 6843: 6842: 6830: 6193: (archived February 6, 2006) 6053:from the original on 2019-05-17. 5682:Sylvester, James Joseph (1878). 5571:Journal de l'École Polytechnique 5399:Rosen, Kenneth H. (2011-06-14). 3798:, is finding a fixed graph as a 3431:in a paper published in 1878 in 542: 530: 7879: 7282:Computational complexity theory 6751:Computational complexity theory 5433:Journal of Open Source Software 4166:in graphs may refer to various 3782:There is a large literature on 7066:Network performance evaluation 5439:(51). The Open Journal: 2161. 4245:, a decomposition into as few 3733:Matrix structures include the 3691:Tabular: Graph data structures 2900: 2888: 2881:. Specifically, for each edge 2765: 2753: 2747: 2735: 2727: 2660: 2648: 2642: 2630: 2543: 2531: 2525: 2513: 2488: 2476: 2375: 2363: 2357: 2345: 2337: 2217: 2199: 2160: 2148: 2124: 2112: 1873: 1861: 1831:that is, ordered sequences of 1684: 1672: 1666: 1654: 1582: 1570: 1437: 1425: 1418:. Specifically, for each edge 1265: 1257: 1245:, its number of vertices. The 1231: 1223: 1058: 704: 596: 578: 181: 169: 1: 7437:Multimedia information system 7422:Geographic information system 7412:Enterprise information system 7001:Computer systems organization 5821:Appel, K.; Haken, W. (1977), 5178:10.1080/23311983.2016.1171458 4024:Erdős–Faber–Lovász conjecture 3833:A similar problem is finding 3794:A common problem, called the 3339:The Königsberg Bridge problem 3291:Graph theory is also used in 3250:, notably through the use of 3099:principle of compositionality 2223:{\displaystyle G=(V,E,\phi )} 859:{\displaystyle \{x,x\}=\{x\}} 602:{\displaystyle G=(V,E,\phi )} 7796:Computational social science 7384:Theoretical computer science 7197:Software development process 6973:Electronic design automation 6958:Very Large Scale Integration 6256:(2006) by Hartmann and Weigt 5788:, p. 26, archived from 5629:10.1017/CBO9780511703690.046 5257:10.1212/WNL.0b013e31829a33f8 5165:Cogent Arts & Humanities 4934:Bender & Williamson 2010 4910:Bender & Williamson 2010 4885:Bender & Williamson 2010 4656:Related areas of mathematics 4598:Planarity testing algorithms 4334:Publications in graph theory 4019:Strong perfect graph theorem 3796:subgraph isomorphism problem 3722:List structures include the 3593:, who published in 1845 his 38:Area of discrete mathematics 7619:Natural language processing 7407:Information storage systems 6158:Encyclopedia of Mathematics 5290:Relativistic Quantum Fields 5007:European Physical Journal B 4694:Abstract simplicial complex 4588:Nearest neighbour algorithm 4366:Disjoint-set data structure 4324:List of graph theory topics 4101:Seven bridges of Königsberg 4052:Subsumption and unification 3445:precisely identical with a 3349:Seven Bridges of Königsberg 3227:Graph theory in sociology: 3121:are therefore important in 1279:, its number of edges. The 8040: 7535:Human–computer interaction 7505:Intrusion detection system 7417:Social information systems 7402:Database management system 6801:Films about mathematicians 6234:A list of graph algorithms 6208:The Social Life of Routers 6119:. Oxford University Press. 6064:Cambridge University Press 5971:. Oxford University Press. 5381:Grandjean, Martin (2015). 5307:Journal of Applied Physics 5202:Brain Imaging and Behavior 5156:Grandjean, Martin (2016). 5135:10.1109/JPROC.2018.2820300 5037:10.1140/epjb/e2004-00301-0 4645:Probabilistic graph theory 4121:Traveling salesman problem 4001: 3950:Kelmans–Seymour conjecture 3697:Graph (abstract data type) 3694: 3642: 3520:, particularly studied by 3242:as a way, for example, to 3195:computational neuroscience 3189:to database searching. In 1527: 122: 26: 7864: 7801:Computational engineering 7776:Computational mathematics 6922: 6824: 6370:Philosophy of mathematics 6310: 6117:Networks: An Introduction 6071:Golumbic, Martin (1980). 6008:Introductory Graph Theory 5921:. SIAM. p. 1171458. 5557:, Oxford University Press 5454:10.1101/2020.03.02.972471 5351:Networks: An Introduction 5214:10.1007/s11682-016-9528-3 4700:Prominent graph theorists 4593:Network simplex algorithm 4069:automatic theorem proving 4029:Total coloring conjecture 3992:reconstruction conjecture 3885:) nor the complete graph 3828:graph isomorphism problem 3123:computational linguistics 2428:mapping every edge to an 778:mapping every edge to an 85:) which are connected by 7811:Computational healthcare 7806:Differentiable computing 7725:Graphics processing unit 7144:Domain-specific language 7013:Computational complexity 6806:Recreational mathematics 6222:, and library resources 6060:Algorithmic Graph Theory 6004:Chartrand, Gary (1985). 5669:10.1002/cber.18750080252 5587:Annales de Mathématiques 4900:, p. 234 or Biggs, p. 4. 4650:Topological graph theory 4563:Ford–Fulkerson algorithm 4558:Floyd–Warshall algorithm 4319:Glossary of graph theory 4141:Max flow min cut theorem 4095:Route inspection problem 4085:Hamiltonian path problem 4039:List coloring conjecture 4035:'s conjecture (unsolved) 3926:complete bipartite graph 3873:complete bipartite graph 3595:Kirchhoff's circuit laws 3244:measure actors' prestige 3167:condensed matter physics 3135:finite-state transducers 3107:typed feature structures 3077:storing and querying of 3055:transformation of graphs 125:Glossary of graph theory 7935:Graph analysis software 7786:Computational chemistry 7720:Photograph manipulation 7611:Artificial intelligence 7427:Decision support system 6691:Mathematical statistics 6681:Mathematical psychology 6651:Engineering mathematics 6585:Algebraic number theory 5969:Graph Theory, 1736–1936 5684:"Chemistry and Algebra" 5574:, 9 (Cahier 16): 66–86. 5554:Graph Theory, 1736-1936 5123:Proceedings of the IEEE 4974:10.1145/2615569.2615684 4568:Hopcroft–Karp algorithm 4501:Strongly regular graphs 4314:Gallery of named graphs 4280:forbidden substructures 4255:, a decomposition of a 3984:point-deleted subgraphs 3848:independent set problem 3657:The pioneering work of 3252:social network analysis 3111:directed acyclic graphs 1588:{\displaystyle G=(V,E)} 1513:{\displaystyle x\sim y} 371:{\displaystyle \{x,y\}} 341:undirected simple graph 187:{\displaystyle G=(V,E)} 131:mathematical structures 69:mathematical structures 7851:Educational technology 7682:Reinforcement learning 7432:Process control system 7330:Computational geometry 7320:Algorithmic efficiency 7315:Analysis of algorithms 6963:Systems on Chip (SoCs) 6837:Mathematics portal 6686:Mathematical sociology 6666:Mathematical economics 6661:Mathematical chemistry 6590:Analytic number theory 6471:Differential equations 6084:Harary, Frank (1969). 6058:Gibbons, Alan (1985). 6027:Deo, Narsingh (1974). 5956:Berge, Claude (1958). 5901:10.1006/jctb.1997.1750 5872:10.1215/ijm/1256049012 5843:10.1215/ijm/1256049011 5616:Philosophical Magazine 4635:Geometric graph theory 4630:Algebraic graph theory 4553:Edmonds–Karp algorithm 4528:Bellman–Ford algorithm 4466:Pebble motion problems 4426:Graph sandwich problem 4346:Algebraic graph theory 4302:for members of a class 4275:the members of a class 4195:Decomposition problems 3769:between two vertices. 3518:factorization problems 3340: 3309:Algebraic graph theory 3235: 3010: 2991: 2971: 2947: 2927: 2907: 2875: 2851: 2827: 2790: 2711:should be modified to 2705: 2685: 2612:should be modified to 2606: 2586: 2495: 2463: 2418: 2285: 2247: 2224: 2167: 2131: 2099: 2079: 2055: 2035: 2008: 1984: 1960: 1940: 1920: 1900: 1880: 1845: 1825: 1794: 1727: 1612: 1589: 1539: 1514: 1484: 1464: 1444: 1412: 1388: 1368: 1345: 1273: 1239: 1205: 1185: 1161: 1141: 1104: 1042:should be modified to 1036: 1016: 960:should be modified to 954: 934: 860: 816: 768: 664: 626: 603: 523: 503: 483: 459: 439: 412: 392: 372: 309: 211: 188: 146: 50: 33:Graph (disambiguation) 31:. For other uses, see 7821:Electronic publishing 7791:Computational biology 7781:Computational physics 7677:Unsupervised learning 7591:Distributed computing 7467:Information retrieval 7374:Mathematical analysis 7364:Mathematical software 7247:Theory of computation 7212:Software construction 7202:Requirements analysis 7080:Software organization 7008:Computer architecture 6978:Hardware acceleration 6943:Printed circuit board 6816:Mathematics education 6746:Theory of computation 6466:Hypercomplex analysis 6214:Graph Theory Software 6187:Image gallery: graphs 6170:Graph theory tutorial 6115:Newman, Mark (2010). 6095:Graphical Enumeration 5348:Newman, Mark (2010). 4741:Dirac, Gabriel Andrew 4640:Extremal graph theory 4496:Spectral graph theory 4486:Random regular graphs 4295:membership in a class 4116:Three-cottage problem 4106:Shortest path problem 4090:Minimum spanning tree 3883:Three-cottage problem 3784:graphical enumeration 3639:Visual: Graph drawing 3535:extremal graph theory 3413:enumeration of graphs 3399:differential calculus 3343:The paper written by 3338: 3311:has close links with 3226: 3204:Chemical graph theory 3153:Physics and chemistry 3079:graph-structured data 3059:graph rewrite systems 3008: 2992: 2972: 2948: 2928: 2908: 2906:{\displaystyle (x,y)} 2876: 2852: 2837:~ on the vertices of 2828: 2791: 2706: 2704:{\displaystyle \phi } 2686: 2607: 2587: 2496: 2494:{\displaystyle (x,x)} 2464: 2419: 2286: 2248: 2225: 2186:is an ordered triple 2168: 2166:{\displaystyle (x,y)} 2132: 2130:{\displaystyle (y,x)} 2100: 2080: 2056: 2036: 2009: 1985: 1961: 1941: 1921: 1901: 1881: 1879:{\displaystyle (x,y)} 1846: 1826: 1795: 1793:{\displaystyle V^{n}} 1771:directed simple graph 1728: 1613: 1590: 1537: 1515: 1485: 1465: 1445: 1443:{\displaystyle (x,y)} 1413: 1389: 1369: 1367:{\displaystyle \sim } 1346: 1274: 1240: 1206: 1186: 1162: 1142: 1105: 1037: 1035:{\displaystyle \phi } 1017: 955: 935: 861: 817: 769: 665: 627: 604: 565:is an ordered triple 521: 504: 484: 460: 440: 413: 393: 373: 310: 212: 189: 144: 123:Further information: 44: 7581:Concurrent computing 7553:Ubiquitous computing 7525:Application security 7520:Information security 7349:Discrete mathematics 7325:Randomized algorithm 7277:Computability theory 7255:Model of computation 7227:Software maintenance 7222:Software engineering 7184:Software development 7134:Programming language 7129:Programming paradigm 7046:Network architecture 6796:Informal mathematics 6676:Mathematical physics 6671:Mathematical finance 6656:Mathematical biology 6595:Diophantine geometry 6204:— a graph theory IDE 5512:10.1093/brain/awz125 5076:10.1093/brain/awz125 4578:Kosaraju's algorithm 4548:Dijkstra's algorithm 4538:Breadth-first search 4511:Transitive reduction 4406:Graph data structure 4371:Dual-phase evolution 4185:Vertex cover problem 4153:Museum guard problem 3914:Kuratowski's Theorem 3900:of a given graph. A 3597:for calculating the 3362:carried on with the 3175:quantum field theory 3063:graph transformation 2981: 2961: 2937: 2917: 2885: 2865: 2841: 2835:homogeneous relation 2817: 2715: 2695: 2616: 2596: 2505: 2473: 2453: 2325: 2275: 2237: 2190: 2145: 2109: 2089: 2069: 2045: 2025: 1998: 1974: 1950: 1930: 1910: 1890: 1858: 1835: 1812: 1777: 1640: 1602: 1561: 1498: 1474: 1454: 1422: 1402: 1378: 1358: 1353:homogeneous relation 1335: 1253: 1219: 1195: 1175: 1151: 1131: 1046: 1026: 964: 944: 870: 826: 806: 692: 654: 616: 569: 493: 473: 449: 429: 402: 382: 350: 239: 201: 160: 113:discrete mathematics 7856:Document management 7846:Operations research 7771:Enterprise software 7687:Multi-task learning 7672:Supervised learning 7394:Information systems 7217:Software deployment 7174:Software repository 7028:Real-time computing 6811:Mathematics and art 6721:Operations research 6476:Functional analysis 5700:1878Natur..17..284S 5651:Cayley, A. (1875), 5464:10.21105/joss.02161 5445:2020JOSS....5.2161K 5319:2016JAP...119a5102K 5029:2004EPJB...41..113M 4966:2013arXiv1312.0976H 4950:. pp. 99–108. 4786:Heawood, Percy John 4766:Fleischner, Herbert 4746:Dijkstra, Edsger W. 4618:Topological sorting 4583:Kruskal's algorithm 4573:Hungarian algorithm 4533:Borůvka's algorithm 4516:Tree data structure 4253:Graph factorization 4147:Visibility problems 3812:NP-complete problem 3755:Kirchhoff's theorem 3623:random graph theory 3453:for constructing a 3191:statistical physics 3061:. Complementary to 2857:that is called the 2438:directed multigraph 1800:denotes the set of 1557:is an ordered pair 1394:that is called the 1374:on the vertices of 1351:induce a symmetric 1272:{\displaystyle |E|} 1238:{\displaystyle |V|} 29:Graph of a function 7639:Search methodology 7586:Parallel computing 7543:Interaction design 7452:Computing platform 7379:Numerical analysis 7369:Information theory 7154:Software framework 7117:Software notations 7056:Network components 6953:Integrated circuit 6756:Numerical analysis 6365:Mathematical logic 6360:Information theory 6239:2019-07-13 at the 6230:about graph theory 6228:in other libraries 6175:2012-01-16 at the 4851:Thomassen, Carsten 4811:Nešetřil, Jaroslav 4726:Brightwell, Graham 4721:Bondy, Adrian John 4543:Depth-first search 4471:Percolation theory 4436:Intersection graph 4391:Graph automorphism 4287:Finding efficient 4237:Cycle double cover 4168:set cover problems 4014:Four-color theorem 3960:graph that is not 3958:5-vertex-connected 3681:intersection graph 3478:four color problem 3341: 3236: 3213:percolation theory 3011: 2987: 2967: 2943: 2923: 2903: 2871: 2859:adjacency relation 2847: 2823: 2786: 2701: 2681: 2602: 2582: 2491: 2459: 2426:incidence function 2414: 2281: 2243: 2220: 2163: 2127: 2095: 2075: 2051: 2031: 2004: 1980: 1956: 1936: 1916: 1896: 1876: 1841: 1824:{\displaystyle V,} 1821: 1790: 1723: 1608: 1585: 1540: 1510: 1480: 1460: 1440: 1408: 1396:adjacency relation 1384: 1364: 1341: 1269: 1235: 1201: 1181: 1157: 1137: 1100: 1032: 1012: 950: 930: 856: 812: 776:incidence function 764: 660: 622: 599: 524: 499: 479: 455: 435: 408: 388: 368: 305: 207: 184: 147: 51: 8011: 8010: 7902: 7901: 7831:Electronic voting 7761:Quantum Computing 7754:Applied computing 7740:Image compression 7510:Hardware security 7500:Security services 7457:Digital marketing 7237:Open-source model 7149:Modeling language 7061:Network scheduler 6882: 6881: 6481:Harmonic analysis 6137:978-0-898719-90-1 5987:978-1-84628-969-9 5928:978-0-898719-90-1 5859:Illinois J. Math. 5830:Illinois J. Math. 5739:978-0-521-79489-3 5410:978-0-07-338309-5 5387:Who Shall Survive 5327:10.1063/1.4939280 4731:Chudnovsky, Maria 4491:Semantic networks 4381:Existential graph 4164:Covering problems 4159:Covering problems 4134:flows in networks 4071:and modeling the 3835:induced subgraphs 3757:on the number of 3607:electric circuits 3273:molecular biology 3127:optimality theory 3119:semantic networks 3115:lexical semantics 2990:{\displaystyle y} 2970:{\displaystyle x} 2946:{\displaystyle y} 2926:{\displaystyle x} 2874:{\displaystyle G} 2850:{\displaystyle G} 2826:{\displaystyle G} 2605:{\displaystyle E} 2564: 2462:{\displaystyle x} 2396: 2284:{\displaystyle E} 2246:{\displaystyle V} 2098:{\displaystyle y} 2078:{\displaystyle x} 2054:{\displaystyle y} 2034:{\displaystyle x} 2007:{\displaystyle y} 1983:{\displaystyle x} 1959:{\displaystyle y} 1939:{\displaystyle x} 1919:{\displaystyle y} 1899:{\displaystyle x} 1844:{\displaystyle n} 1705: 1611:{\displaystyle V} 1483:{\displaystyle y} 1463:{\displaystyle x} 1411:{\displaystyle G} 1387:{\displaystyle G} 1344:{\displaystyle G} 1204:{\displaystyle E} 1184:{\displaystyle V} 1160:{\displaystyle E} 1140:{\displaystyle V} 1125:), respectively. 953:{\displaystyle E} 914: 815:{\displaystyle x} 748: 663:{\displaystyle E} 625:{\displaystyle V} 502:{\displaystyle y} 482:{\displaystyle x} 458:{\displaystyle y} 438:{\displaystyle x} 411:{\displaystyle y} 391:{\displaystyle x} 289: 210:{\displaystyle V} 105:undirected graphs 16:(Redirected from 8031: 7929: 7922: 7915: 7906: 7892: 7891: 7882: 7881: 7872: 7871: 7692:Cross-validation 7664:Machine learning 7548:Social computing 7515:Network security 7310:Algorithm design 7232:Programming team 7192:Control variable 7169:Software library 7107:Software quality 7102:Operating system 7051:Network protocol 6916:Computer science 6909: 6902: 6895: 6886: 6870: 6869: 6858: 6857: 6846: 6845: 6835: 6834: 6766:Computer algebra 6741:Computer science 6461:Complex analysis 6295: 6288: 6281: 6272: 6248:Online textbooks 6166: 6141: 6120: 6111: 6098: 6089: 6080: 6067: 6054: 6052: 6035: 6023: 6011: 6000: 5991: 5972: 5961: 5952: 5933: 5932: 5912: 5906: 5905: 5903: 5883: 5877: 5876: 5874: 5854: 5848: 5847: 5845: 5827: 5818: 5812: 5809: 5803: 5802: 5801: 5800: 5794: 5787: 5773: 5767: 5766: 5755: 5749: 5748: 5747: 5746: 5720: 5714: 5713: 5711: 5709:10.1038/017284a0 5679: 5673: 5672: 5663:(2): 1056–1059, 5648: 5642: 5641: 5612: 5601: 5595: 5594: 5582: 5576: 5575: 5565: 5559: 5558: 5548: 5542: 5541: 5531: 5506:(7): 1955–1972. 5491: 5485: 5484: 5466: 5456: 5430: 5421: 5415: 5414: 5396: 5390: 5379: 5373: 5372: 5370: 5369: 5363: 5356: 5345: 5339: 5338: 5302: 5296: 5295: 5293: 5283: 5277: 5276: 5240: 5234: 5233: 5197: 5191: 5190: 5180: 5162: 5153: 5147: 5146: 5120: 5112: 5106: 5105: 5095: 5070:(7): 1955–1972. 5055: 5049: 5048: 5022: 5020:cond-mat/0304207 5002: 4996: 4995: 4959: 4943: 4937: 4931: 4922: 4919: 4913: 4907: 4901: 4894: 4888: 4882: 4866:Whitney, Hassler 4841:Szemerédi, Endre 4771:Golumbic, Martin 4603:Prim's algorithm 4506:Symmetric graphs 4376:Entitative graph 4356:Conceptual graph 4222: 4215: 3968:of the 5-vertex 3861:Wagner's Theorem 3804:graph properties 3761:of a graph. The 3747:Laplacian matrix 3739:adjacency matrix 3735:incidence matrix 3685:adjacency matrix 3591:Gustav Kirchhoff 3187:chemical editors 3033:computer science 3027:Computer science 2996: 2994: 2993: 2988: 2976: 2974: 2973: 2968: 2952: 2950: 2949: 2944: 2932: 2930: 2929: 2924: 2913:, its endpoints 2912: 2910: 2909: 2904: 2880: 2878: 2877: 2872: 2856: 2854: 2853: 2848: 2832: 2830: 2829: 2824: 2810:) respectively. 2795: 2793: 2792: 2787: 2785: 2781: 2780: 2779: 2710: 2708: 2707: 2702: 2690: 2688: 2687: 2682: 2680: 2676: 2675: 2674: 2611: 2609: 2608: 2603: 2591: 2589: 2588: 2583: 2581: 2577: 2566: 2565: 2562: 2558: 2557: 2501:which is not in 2500: 2498: 2497: 2492: 2468: 2466: 2465: 2460: 2423: 2421: 2420: 2415: 2413: 2409: 2398: 2397: 2394: 2390: 2389: 2290: 2288: 2287: 2282: 2252: 2250: 2249: 2244: 2229: 2227: 2226: 2221: 2172: 2170: 2169: 2164: 2136: 2134: 2133: 2128: 2104: 2102: 2101: 2096: 2084: 2082: 2081: 2076: 2060: 2058: 2057: 2052: 2040: 2038: 2037: 2032: 2013: 2011: 2010: 2005: 1994:of the edge and 1989: 1987: 1986: 1981: 1965: 1963: 1962: 1957: 1945: 1943: 1942: 1937: 1925: 1923: 1922: 1917: 1905: 1903: 1902: 1897: 1885: 1883: 1882: 1877: 1850: 1848: 1847: 1842: 1830: 1828: 1827: 1822: 1803: 1799: 1797: 1796: 1791: 1789: 1788: 1732: 1730: 1729: 1724: 1722: 1718: 1707: 1706: 1703: 1699: 1698: 1617: 1615: 1614: 1609: 1594: 1592: 1591: 1586: 1519: 1517: 1516: 1511: 1489: 1487: 1486: 1481: 1469: 1467: 1466: 1461: 1450:, its endpoints 1449: 1447: 1446: 1441: 1417: 1415: 1414: 1409: 1393: 1391: 1390: 1385: 1373: 1371: 1370: 1365: 1350: 1348: 1347: 1342: 1327: 1325: 1324: 1321: 1318: 1304: 1278: 1276: 1275: 1270: 1268: 1260: 1244: 1242: 1241: 1236: 1234: 1226: 1210: 1208: 1207: 1202: 1190: 1188: 1187: 1182: 1166: 1164: 1163: 1158: 1146: 1144: 1143: 1138: 1118:(sometimes also 1109: 1107: 1106: 1101: 1041: 1039: 1038: 1033: 1021: 1019: 1018: 1013: 959: 957: 956: 951: 939: 937: 936: 931: 916: 915: 912: 866:which is not in 865: 863: 862: 857: 821: 819: 818: 813: 773: 771: 770: 765: 750: 749: 746: 669: 667: 666: 661: 631: 629: 628: 623: 608: 606: 605: 600: 546: 534: 508: 506: 505: 500: 488: 486: 485: 480: 464: 462: 461: 456: 444: 442: 441: 436: 417: 415: 414: 409: 397: 395: 394: 389: 377: 375: 374: 369: 314: 312: 311: 306: 291: 290: 287: 216: 214: 213: 208: 193: 191: 190: 185: 61:is the study of 21: 8039: 8038: 8034: 8033: 8032: 8030: 8029: 8028: 8014: 8013: 8012: 8007: 7984: 7936: 7933: 7903: 7898: 7889: 7860: 7841:Word processing 7749: 7735:Virtual reality 7696: 7658: 7629:Computer vision 7605: 7601:Multiprocessing 7567: 7529: 7495:Security hacker 7471: 7447:Digital library 7388: 7339:Mathematics of 7334: 7296: 7272:Automata theory 7267:Formal language 7241: 7207:Software design 7178: 7111: 7097:Virtual machine 7075: 7071:Network service 7032: 7023:Embedded system 6996: 6929: 6918: 6913: 6883: 6878: 6829: 6820: 6770: 6727: 6706:Systems science 6637: 6633:Homotopy theory 6599: 6566: 6518: 6490: 6437: 6384: 6355:Category theory 6341: 6306: 6299: 6250: 6241:Wayback Machine 6224:in your library 6191:Wayback Machine 6177:Wayback Machine 6151: 6148: 6138: 6123: 6114: 6101: 6092: 6083: 6070: 6057: 6050: 6044: 6033: 6026: 6020: 6003: 5994: 5988: 5975: 5966: 5960:. Paris: Dunod. 5955: 5944: 5941: 5936: 5929: 5914: 5913: 5909: 5885: 5884: 5880: 5856: 5855: 5851: 5825: 5820: 5819: 5815: 5810: 5806: 5798: 5796: 5792: 5785: 5775: 5774: 5770: 5759:Gardner, Martin 5757: 5756: 5752: 5744: 5742: 5740: 5722: 5721: 5717: 5681: 5680: 5676: 5650: 5649: 5645: 5639: 5623:(85): 172–176, 5603: 5602: 5598: 5584: 5583: 5579: 5567: 5566: 5562: 5550: 5549: 5545: 5493: 5492: 5488: 5428: 5423: 5422: 5418: 5411: 5398: 5397: 5393: 5380: 5376: 5367: 5365: 5361: 5354: 5347: 5346: 5342: 5304: 5303: 5299: 5285: 5284: 5280: 5242: 5241: 5237: 5199: 5198: 5194: 5160: 5155: 5154: 5150: 5114: 5113: 5109: 5057: 5056: 5052: 5004: 5003: 4999: 4984: 4945: 4944: 4940: 4932: 4925: 4920: 4916: 4908: 4904: 4895: 4891: 4883: 4879: 4875: 4870: 4826:Robertson, Neil 4821:Ringel, Gerhard 4806:Murty, U. S. R. 4756:Euler, Leonhard 4702: 4685: 4683:Generalizations 4658: 4626: 4524: 4421:Graph rewriting 4342: 4309: 4300:representations 4266: 4217: 4210: 4208: 4197: 4161: 4149: 4136:, for example: 4130: 4081: 4054: 4006: 4000: 3986:. For example: 3977: 3943: 3933: 3912:. For example, 3891: 3880: 3844:independent set 3814:. For example: 3792: 3780: 3775: 3763:distance matrix 3699: 3693: 3677:circle packings 3666:crossing number 3647: 3641: 3632: 3543:Heinrich Heesch 3482:Francis Guthrie 3333: 3325:weighted graphs 3321: 3301: 3261: 3248:rumor spreading 3221: 3219:Social sciences 3208:molecular graph 3155: 3087: 3069:geared towards 3067:graph databases 3029: 3021:network science 3003: 2979: 2978: 2959: 2958: 2953:are said to be 2935: 2934: 2915: 2914: 2883: 2882: 2863: 2862: 2839: 2838: 2815: 2814: 2771: 2734: 2730: 2713: 2712: 2693: 2692: 2666: 2629: 2625: 2614: 2613: 2594: 2593: 2549: 2512: 2508: 2503: 2502: 2471: 2470: 2451: 2450: 2381: 2344: 2340: 2323: 2322: 2273: 2272: 2235: 2234: 2188: 2187: 2143: 2142: 2107: 2106: 2087: 2086: 2067: 2066: 2043: 2042: 2023: 2022: 1996: 1995: 1972: 1971: 1966:are called the 1948: 1947: 1928: 1927: 1926:, the vertices 1908: 1907: 1888: 1887: 1856: 1855: 1833: 1832: 1810: 1809: 1808:of elements of 1801: 1780: 1775: 1774: 1690: 1653: 1649: 1638: 1637: 1600: 1599: 1559: 1558: 1532: 1526: 1496: 1495: 1490:are said to be 1472: 1471: 1452: 1451: 1420: 1419: 1400: 1399: 1376: 1375: 1356: 1355: 1333: 1332: 1322: 1319: 1309: 1308: 1306: 1299: 1251: 1250: 1217: 1216: 1193: 1192: 1173: 1172: 1149: 1148: 1129: 1128: 1044: 1043: 1024: 1023: 962: 961: 942: 941: 868: 867: 824: 823: 804: 803: 690: 689: 652: 651: 614: 613: 567: 566: 559: 558: 557: 556: 552: 551: 550: 547: 539: 538: 535: 491: 490: 471: 470: 447: 446: 427: 426: 418:are called the 400: 399: 380: 379: 378:, the vertices 348: 347: 333:unordered pairs 237: 236: 199: 198: 158: 157: 139: 127: 121: 109:directed graphs 39: 36: 23: 22: 18:Graph-theoretic 15: 12: 11: 5: 8037: 8035: 8027: 8026: 8016: 8015: 8009: 8008: 8006: 8005: 8000: 7994: 7992: 7986: 7985: 7983: 7982: 7977: 7972: 7967: 7962: 7957: 7952: 7946: 7944: 7938: 7937: 7934: 7932: 7931: 7924: 7917: 7909: 7900: 7899: 7897: 7896: 7886: 7876: 7865: 7862: 7861: 7859: 7858: 7853: 7848: 7843: 7838: 7833: 7828: 7823: 7818: 7813: 7808: 7803: 7798: 7793: 7788: 7783: 7778: 7773: 7768: 7763: 7757: 7755: 7751: 7750: 7748: 7747: 7745:Solid modeling 7742: 7737: 7732: 7727: 7722: 7717: 7712: 7706: 7704: 7698: 7697: 7695: 7694: 7689: 7684: 7679: 7674: 7668: 7666: 7660: 7659: 7657: 7656: 7651: 7646: 7644:Control method 7641: 7636: 7631: 7626: 7621: 7615: 7613: 7607: 7606: 7604: 7603: 7598: 7596:Multithreading 7593: 7588: 7583: 7577: 7575: 7569: 7568: 7566: 7565: 7560: 7555: 7550: 7545: 7539: 7537: 7531: 7530: 7528: 7527: 7522: 7517: 7512: 7507: 7502: 7497: 7492: 7490:Formal methods 7487: 7481: 7479: 7473: 7472: 7470: 7469: 7464: 7462:World Wide Web 7459: 7454: 7449: 7444: 7439: 7434: 7429: 7424: 7419: 7414: 7409: 7404: 7398: 7396: 7390: 7389: 7387: 7386: 7381: 7376: 7371: 7366: 7361: 7356: 7351: 7345: 7343: 7336: 7335: 7333: 7332: 7327: 7322: 7317: 7312: 7306: 7304: 7298: 7297: 7295: 7294: 7289: 7284: 7279: 7274: 7269: 7264: 7263: 7262: 7251: 7249: 7243: 7242: 7240: 7239: 7234: 7229: 7224: 7219: 7214: 7209: 7204: 7199: 7194: 7188: 7186: 7180: 7179: 7177: 7176: 7171: 7166: 7161: 7156: 7151: 7146: 7141: 7136: 7131: 7125: 7123: 7113: 7112: 7110: 7109: 7104: 7099: 7094: 7089: 7083: 7081: 7077: 7076: 7074: 7073: 7068: 7063: 7058: 7053: 7048: 7042: 7040: 7034: 7033: 7031: 7030: 7025: 7020: 7015: 7010: 7004: 7002: 6998: 6997: 6995: 6994: 6985: 6980: 6975: 6970: 6965: 6960: 6955: 6950: 6945: 6939: 6937: 6931: 6930: 6923: 6920: 6919: 6914: 6912: 6911: 6904: 6897: 6889: 6880: 6879: 6877: 6876: 6864: 6852: 6840: 6825: 6822: 6821: 6819: 6818: 6813: 6808: 6803: 6798: 6793: 6792: 6791: 6784:Mathematicians 6780: 6778: 6776:Related topics 6772: 6771: 6769: 6768: 6763: 6758: 6753: 6748: 6743: 6737: 6735: 6729: 6728: 6726: 6725: 6724: 6723: 6718: 6713: 6711:Control theory 6703: 6698: 6693: 6688: 6683: 6678: 6673: 6668: 6663: 6658: 6653: 6647: 6645: 6639: 6638: 6636: 6635: 6630: 6625: 6620: 6615: 6609: 6607: 6601: 6600: 6598: 6597: 6592: 6587: 6582: 6576: 6574: 6568: 6567: 6565: 6564: 6559: 6554: 6549: 6544: 6539: 6534: 6528: 6526: 6520: 6519: 6517: 6516: 6511: 6506: 6500: 6498: 6492: 6491: 6489: 6488: 6486:Measure theory 6483: 6478: 6473: 6468: 6463: 6458: 6453: 6447: 6445: 6439: 6438: 6436: 6435: 6430: 6425: 6420: 6415: 6410: 6405: 6400: 6394: 6392: 6386: 6385: 6383: 6382: 6377: 6372: 6367: 6362: 6357: 6351: 6349: 6343: 6342: 6340: 6339: 6334: 6329: 6328: 6327: 6322: 6311: 6308: 6307: 6300: 6298: 6297: 6290: 6283: 6275: 6269: 6268: 6263: 6257: 6249: 6246: 6245: 6244: 6231: 6217: 6211: 6205: 6199: 6194: 6184: 6179: 6167: 6153:"Graph theory" 6147: 6146:External links 6144: 6143: 6142: 6136: 6121: 6112: 6099: 6090: 6081: 6077:Academic Press 6068: 6055: 6042: 6024: 6018: 6001: 5992: 5986: 5973: 5964: 5953: 5940: 5937: 5935: 5934: 5927: 5907: 5878: 5865:(3): 491–567, 5849: 5836:(3): 429–490, 5813: 5804: 5768: 5750: 5738: 5715: 5674: 5643: 5637: 5596: 5577: 5560: 5543: 5486: 5416: 5409: 5391: 5374: 5340: 5297: 5278: 5251:(2): 134–143. 5235: 5208:(2): 473–485. 5192: 5171:(1): 1171458. 5148: 5129:(5): 784–786. 5107: 5050: 5013:(1): 113–121. 4997: 4982: 4938: 4936:, p. 161. 4923: 4914: 4912:, p. 149. 4902: 4889: 4887:, p. 148. 4876: 4874: 4871: 4869: 4868: 4863: 4858: 4853: 4848: 4843: 4838: 4836:Sudakov, Benny 4833: 4828: 4823: 4818: 4813: 4808: 4803: 4801:Lovász, László 4798: 4793: 4788: 4783: 4778: 4776:Graham, Ronald 4773: 4768: 4763: 4761:Faudree, Ralph 4758: 4753: 4748: 4743: 4738: 4733: 4728: 4723: 4718: 4716:Bollobás, Béla 4713: 4708: 4701: 4698: 4697: 4696: 4691: 4684: 4681: 4680: 4679: 4674: 4669: 4664: 4657: 4654: 4653: 4652: 4647: 4642: 4637: 4632: 4625: 4622: 4621: 4620: 4615: 4610: 4605: 4600: 4595: 4590: 4585: 4580: 4575: 4570: 4565: 4560: 4555: 4550: 4545: 4540: 4535: 4530: 4523: 4520: 4519: 4518: 4513: 4508: 4503: 4498: 4493: 4488: 4483: 4478: 4473: 4468: 4463: 4458: 4456:Network theory 4453: 4448: 4443: 4438: 4433: 4431:Graph property 4428: 4423: 4418: 4416:Graph equation 4413: 4408: 4403: 4401:Graph database 4398: 4396:Graph coloring 4393: 4388: 4383: 4378: 4373: 4368: 4363: 4361:Data structure 4358: 4353: 4351:Citation graph 4348: 4341: 4340:Related topics 4338: 4337: 4336: 4331: 4326: 4321: 4316: 4310: 4308: 4305: 4304: 4303: 4296: 4285: 4282: 4276: 4265: 4262: 4261: 4260: 4250: 4240: 4234: 4204: 4196: 4193: 4192: 4191: 4188: 4182: 4175:Dominating set 4160: 4157: 4156: 4155: 4148: 4145: 4144: 4143: 4129: 4126: 4125: 4124: 4118: 4113: 4108: 4103: 4098: 4092: 4087: 4080: 4079:Route problems 4077: 4053: 4050: 4049: 4048: 4042: 4036: 4031:, also called 4026: 4021: 4016: 4004:Graph coloring 4002:Main article: 3999: 3998:Graph coloring 3996: 3995: 3994: 3980: 3979: 3975: 3970:complete graph 3946: 3945: 3941: 3936:complete graph 3931: 3894: 3893: 3889: 3878: 3852: 3851: 3850:(NP-complete). 3846:is called the 3824: 3823: 3822:(NP-complete). 3820:clique problem 3791: 3788: 3779: 3776: 3774: 3771: 3759:spanning trees 3728:adjacency list 3703:data structure 3695:Main article: 3692: 3689: 3643:Main article: 3640: 3637: 3631: 3630:Representation 3628: 3551:Wolfgang Haken 3459: 3458: 3364:analysis situs 3358:knight problem 3345:Leonhard Euler 3332: 3329: 3320: 3317: 3300: 3297: 3260: 3257: 3246:or to explore 3220: 3217: 3154: 3151: 3149:, and others. 3131:lattice graphs 3086: 3083: 3028: 3025: 3002: 2999: 2986: 2966: 2942: 2922: 2902: 2899: 2896: 2893: 2890: 2870: 2846: 2822: 2784: 2778: 2774: 2770: 2767: 2764: 2761: 2758: 2755: 2752: 2749: 2746: 2743: 2740: 2737: 2733: 2729: 2726: 2723: 2720: 2700: 2679: 2673: 2669: 2665: 2662: 2659: 2656: 2653: 2650: 2647: 2644: 2641: 2638: 2635: 2632: 2628: 2624: 2621: 2601: 2580: 2576: 2573: 2570: 2556: 2552: 2548: 2545: 2542: 2539: 2536: 2533: 2530: 2527: 2524: 2521: 2518: 2515: 2511: 2490: 2487: 2484: 2481: 2478: 2458: 2434: 2433: 2412: 2408: 2405: 2402: 2388: 2384: 2380: 2377: 2374: 2371: 2368: 2365: 2362: 2359: 2356: 2353: 2350: 2347: 2343: 2339: 2336: 2333: 2330: 2320: 2309:directed lines 2305:directed links 2301:directed edges 2280: 2270: 2242: 2219: 2216: 2213: 2210: 2207: 2204: 2201: 2198: 2195: 2184:directed graph 2176:Multiple edges 2162: 2159: 2156: 2153: 2150: 2137:is called the 2126: 2123: 2120: 2117: 2114: 2094: 2074: 2050: 2030: 2003: 1979: 1955: 1935: 1915: 1895: 1886:directed from 1875: 1872: 1869: 1866: 1863: 1840: 1820: 1817: 1787: 1783: 1767: 1766: 1751:directed lines 1747:directed links 1743:directed edges 1721: 1717: 1714: 1711: 1697: 1693: 1689: 1686: 1683: 1680: 1677: 1674: 1671: 1668: 1665: 1662: 1659: 1656: 1652: 1648: 1645: 1635: 1607: 1584: 1581: 1578: 1575: 1572: 1569: 1566: 1555:directed graph 1544:directed graph 1530:Directed graph 1528:Main article: 1525: 1524:Directed graph 1522: 1509: 1506: 1503: 1479: 1459: 1439: 1436: 1433: 1430: 1427: 1407: 1383: 1363: 1340: 1267: 1263: 1259: 1249:of a graph is 1233: 1229: 1225: 1215:of a graph is 1200: 1180: 1156: 1136: 1099: 1096: 1093: 1090: 1087: 1084: 1081: 1078: 1075: 1072: 1069: 1066: 1063: 1060: 1057: 1054: 1051: 1031: 1011: 1008: 1005: 1002: 999: 996: 993: 990: 987: 984: 981: 978: 975: 972: 969: 949: 929: 926: 923: 920: 908: 905: 902: 899: 896: 893: 890: 887: 884: 881: 878: 875: 855: 852: 849: 846: 843: 840: 837: 834: 831: 811: 784: 783: 780:unordered pair 763: 760: 757: 754: 742: 739: 736: 733: 730: 727: 724: 721: 718: 715: 712: 709: 706: 703: 700: 697: 687: 659: 649: 621: 598: 595: 592: 589: 586: 583: 580: 577: 574: 554: 553: 548: 541: 540: 536: 529: 528: 527: 526: 525: 512:multiple edges 498: 478: 454: 434: 407: 387: 367: 364: 361: 358: 355: 337: 336: 304: 301: 298: 295: 283: 280: 277: 274: 271: 268: 265: 262: 259: 256: 253: 250: 247: 244: 234: 206: 183: 180: 177: 174: 171: 168: 165: 138: 135: 120: 117: 37: 24: 14: 13: 10: 9: 6: 4: 3: 2: 8036: 8025: 8022: 8021: 8019: 8004: 8001: 7999: 7996: 7995: 7993: 7991: 7987: 7981: 7978: 7976: 7973: 7971: 7968: 7966: 7963: 7961: 7958: 7956: 7953: 7951: 7948: 7947: 7945: 7943: 7939: 7930: 7925: 7923: 7918: 7916: 7911: 7910: 7907: 7895: 7887: 7885: 7877: 7875: 7867: 7866: 7863: 7857: 7854: 7852: 7849: 7847: 7844: 7842: 7839: 7837: 7834: 7832: 7829: 7827: 7824: 7822: 7819: 7817: 7814: 7812: 7809: 7807: 7804: 7802: 7799: 7797: 7794: 7792: 7789: 7787: 7784: 7782: 7779: 7777: 7774: 7772: 7769: 7767: 7764: 7762: 7759: 7758: 7756: 7752: 7746: 7743: 7741: 7738: 7736: 7733: 7731: 7730:Mixed reality 7728: 7726: 7723: 7721: 7718: 7716: 7713: 7711: 7708: 7707: 7705: 7703: 7699: 7693: 7690: 7688: 7685: 7683: 7680: 7678: 7675: 7673: 7670: 7669: 7667: 7665: 7661: 7655: 7652: 7650: 7647: 7645: 7642: 7640: 7637: 7635: 7632: 7630: 7627: 7625: 7622: 7620: 7617: 7616: 7614: 7612: 7608: 7602: 7599: 7597: 7594: 7592: 7589: 7587: 7584: 7582: 7579: 7578: 7576: 7574: 7570: 7564: 7563:Accessibility 7561: 7559: 7558:Visualization 7556: 7554: 7551: 7549: 7546: 7544: 7541: 7540: 7538: 7536: 7532: 7526: 7523: 7521: 7518: 7516: 7513: 7511: 7508: 7506: 7503: 7501: 7498: 7496: 7493: 7491: 7488: 7486: 7483: 7482: 7480: 7478: 7474: 7468: 7465: 7463: 7460: 7458: 7455: 7453: 7450: 7448: 7445: 7443: 7440: 7438: 7435: 7433: 7430: 7428: 7425: 7423: 7420: 7418: 7415: 7413: 7410: 7408: 7405: 7403: 7400: 7399: 7397: 7395: 7391: 7385: 7382: 7380: 7377: 7375: 7372: 7370: 7367: 7365: 7362: 7360: 7357: 7355: 7352: 7350: 7347: 7346: 7344: 7342: 7337: 7331: 7328: 7326: 7323: 7321: 7318: 7316: 7313: 7311: 7308: 7307: 7305: 7303: 7299: 7293: 7290: 7288: 7285: 7283: 7280: 7278: 7275: 7273: 7270: 7268: 7265: 7261: 7258: 7257: 7256: 7253: 7252: 7250: 7248: 7244: 7238: 7235: 7233: 7230: 7228: 7225: 7223: 7220: 7218: 7215: 7213: 7210: 7208: 7205: 7203: 7200: 7198: 7195: 7193: 7190: 7189: 7187: 7185: 7181: 7175: 7172: 7170: 7167: 7165: 7162: 7160: 7157: 7155: 7152: 7150: 7147: 7145: 7142: 7140: 7137: 7135: 7132: 7130: 7127: 7126: 7124: 7122: 7118: 7114: 7108: 7105: 7103: 7100: 7098: 7095: 7093: 7090: 7088: 7085: 7084: 7082: 7078: 7072: 7069: 7067: 7064: 7062: 7059: 7057: 7054: 7052: 7049: 7047: 7044: 7043: 7041: 7039: 7035: 7029: 7026: 7024: 7021: 7019: 7018:Dependability 7016: 7014: 7011: 7009: 7006: 7005: 7003: 6999: 6993: 6989: 6986: 6984: 6981: 6979: 6976: 6974: 6971: 6969: 6966: 6964: 6961: 6959: 6956: 6954: 6951: 6949: 6946: 6944: 6941: 6940: 6938: 6936: 6932: 6927: 6921: 6917: 6910: 6905: 6903: 6898: 6896: 6891: 6890: 6887: 6875: 6874: 6865: 6863: 6862: 6853: 6851: 6850: 6841: 6839: 6838: 6833: 6827: 6826: 6823: 6817: 6814: 6812: 6809: 6807: 6804: 6802: 6799: 6797: 6794: 6790: 6787: 6786: 6785: 6782: 6781: 6779: 6777: 6773: 6767: 6764: 6762: 6759: 6757: 6754: 6752: 6749: 6747: 6744: 6742: 6739: 6738: 6736: 6734: 6733:Computational 6730: 6722: 6719: 6717: 6714: 6712: 6709: 6708: 6707: 6704: 6702: 6699: 6697: 6694: 6692: 6689: 6687: 6684: 6682: 6679: 6677: 6674: 6672: 6669: 6667: 6664: 6662: 6659: 6657: 6654: 6652: 6649: 6648: 6646: 6644: 6640: 6634: 6631: 6629: 6626: 6624: 6621: 6619: 6616: 6614: 6611: 6610: 6608: 6606: 6602: 6596: 6593: 6591: 6588: 6586: 6583: 6581: 6578: 6577: 6575: 6573: 6572:Number theory 6569: 6563: 6560: 6558: 6555: 6553: 6550: 6548: 6545: 6543: 6540: 6538: 6535: 6533: 6530: 6529: 6527: 6525: 6521: 6515: 6512: 6510: 6507: 6505: 6504:Combinatorics 6502: 6501: 6499: 6497: 6493: 6487: 6484: 6482: 6479: 6477: 6474: 6472: 6469: 6467: 6464: 6462: 6459: 6457: 6456:Real analysis 6454: 6452: 6449: 6448: 6446: 6444: 6440: 6434: 6431: 6429: 6426: 6424: 6421: 6419: 6416: 6414: 6411: 6409: 6406: 6404: 6401: 6399: 6396: 6395: 6393: 6391: 6387: 6381: 6378: 6376: 6373: 6371: 6368: 6366: 6363: 6361: 6358: 6356: 6353: 6352: 6350: 6348: 6344: 6338: 6335: 6333: 6330: 6326: 6323: 6321: 6318: 6317: 6316: 6313: 6312: 6309: 6304: 6296: 6291: 6289: 6284: 6282: 6277: 6276: 6273: 6267: 6264: 6261: 6258: 6255: 6252: 6251: 6247: 6242: 6238: 6235: 6232: 6229: 6225: 6221: 6218: 6215: 6212: 6209: 6206: 6203: 6200: 6198: 6195: 6192: 6188: 6185: 6183: 6180: 6178: 6174: 6171: 6168: 6164: 6160: 6159: 6154: 6150: 6149: 6145: 6139: 6133: 6129: 6128: 6122: 6118: 6113: 6109: 6108:North-Holland 6105: 6100: 6096: 6091: 6087: 6082: 6078: 6074: 6069: 6065: 6061: 6056: 6049: 6045: 6043:0-13-363473-6 6039: 6032: 6031: 6025: 6021: 6019:0-486-24775-9 6015: 6010: 6009: 6002: 5998: 5993: 5989: 5983: 5979: 5974: 5970: 5965: 5959: 5954: 5950: 5949: 5943: 5942: 5938: 5930: 5924: 5920: 5919: 5911: 5908: 5902: 5897: 5893: 5889: 5882: 5879: 5873: 5868: 5864: 5860: 5853: 5850: 5844: 5839: 5835: 5831: 5824: 5817: 5814: 5808: 5805: 5795:on 2016-03-05 5791: 5784: 5783: 5778: 5772: 5769: 5764: 5760: 5754: 5751: 5741: 5735: 5731: 5730: 5725: 5719: 5716: 5710: 5705: 5701: 5697: 5693: 5689: 5685: 5678: 5675: 5670: 5666: 5662: 5658: 5654: 5647: 5644: 5640: 5638:9780511703690 5634: 5630: 5626: 5622: 5619:, Series IV, 5618: 5617: 5611: 5606: 5600: 5597: 5592: 5588: 5581: 5578: 5573: 5572: 5564: 5561: 5556: 5555: 5547: 5544: 5539: 5535: 5530: 5525: 5521: 5517: 5513: 5509: 5505: 5501: 5497: 5490: 5487: 5482: 5478: 5474: 5470: 5465: 5460: 5455: 5450: 5446: 5442: 5438: 5434: 5427: 5420: 5417: 5412: 5406: 5402: 5395: 5392: 5388: 5384: 5378: 5375: 5364:on 2020-07-28 5360: 5353: 5352: 5344: 5341: 5336: 5332: 5328: 5324: 5320: 5316: 5313:(1): 015102. 5312: 5308: 5301: 5298: 5292: 5291: 5282: 5279: 5274: 5270: 5266: 5262: 5258: 5254: 5250: 5246: 5239: 5236: 5231: 5227: 5223: 5219: 5215: 5211: 5207: 5203: 5196: 5193: 5188: 5184: 5179: 5174: 5170: 5166: 5159: 5152: 5149: 5144: 5140: 5136: 5132: 5128: 5124: 5119: 5111: 5108: 5103: 5099: 5094: 5089: 5085: 5081: 5077: 5073: 5069: 5065: 5061: 5054: 5051: 5046: 5042: 5038: 5034: 5030: 5026: 5021: 5016: 5012: 5008: 5001: 4998: 4993: 4989: 4985: 4983:9781450326223 4979: 4975: 4971: 4967: 4963: 4958: 4953: 4949: 4942: 4939: 4935: 4930: 4928: 4924: 4918: 4915: 4911: 4906: 4903: 4899: 4893: 4890: 4886: 4881: 4878: 4872: 4867: 4864: 4862: 4859: 4857: 4854: 4852: 4849: 4847: 4846:Thomas, Robin 4844: 4842: 4839: 4837: 4834: 4832: 4831:Seymour, Paul 4829: 4827: 4824: 4822: 4819: 4817: 4816:Rényi, Alfréd 4814: 4812: 4809: 4807: 4804: 4802: 4799: 4797: 4794: 4792: 4791:Kotzig, Anton 4789: 4787: 4784: 4782: 4781:Harary, Frank 4779: 4777: 4774: 4772: 4769: 4767: 4764: 4762: 4759: 4757: 4754: 4752: 4749: 4747: 4744: 4742: 4739: 4737: 4734: 4732: 4729: 4727: 4724: 4722: 4719: 4717: 4714: 4712: 4711:Berge, Claude 4709: 4707: 4704: 4703: 4699: 4695: 4692: 4690: 4687: 4686: 4682: 4678: 4677:Ramsey theory 4675: 4673: 4670: 4668: 4665: 4663: 4662:Combinatorics 4660: 4659: 4655: 4651: 4648: 4646: 4643: 4641: 4638: 4636: 4633: 4631: 4628: 4627: 4623: 4619: 4616: 4614: 4611: 4609: 4606: 4604: 4601: 4599: 4596: 4594: 4591: 4589: 4586: 4584: 4581: 4579: 4576: 4574: 4571: 4569: 4566: 4564: 4561: 4559: 4556: 4554: 4551: 4549: 4546: 4544: 4541: 4539: 4536: 4534: 4531: 4529: 4526: 4525: 4521: 4517: 4514: 4512: 4509: 4507: 4504: 4502: 4499: 4497: 4494: 4492: 4489: 4487: 4484: 4482: 4481:Quantum graph 4479: 4477: 4476:Perfect graph 4474: 4472: 4469: 4467: 4464: 4462: 4459: 4457: 4454: 4452: 4449: 4447: 4446:Logical graph 4444: 4442: 4441:Knight's Tour 4439: 4437: 4434: 4432: 4429: 4427: 4424: 4422: 4419: 4417: 4414: 4412: 4411:Graph drawing 4409: 4407: 4404: 4402: 4399: 4397: 4394: 4392: 4389: 4387: 4386:Graph algebra 4384: 4382: 4379: 4377: 4374: 4372: 4369: 4367: 4364: 4362: 4359: 4357: 4354: 4352: 4349: 4347: 4344: 4343: 4339: 4335: 4332: 4330: 4327: 4325: 4322: 4320: 4317: 4315: 4312: 4311: 4306: 4301: 4297: 4294: 4290: 4286: 4283: 4281: 4277: 4274: 4271: 4270: 4269: 4264:Graph classes 4263: 4258: 4257:regular graph 4254: 4251: 4248: 4244: 4243:Edge coloring 4241: 4238: 4235: 4232: 4229: 4228: 4227: 4224: 4220: 4213: 4207: 4203: 4194: 4189: 4186: 4183: 4180: 4179:neighborhoods 4176: 4173: 4172: 4171: 4169: 4165: 4158: 4154: 4151: 4150: 4146: 4142: 4139: 4138: 4137: 4135: 4127: 4122: 4119: 4117: 4114: 4112: 4109: 4107: 4104: 4102: 4099: 4096: 4093: 4091: 4088: 4086: 4083: 4082: 4078: 4076: 4074: 4070: 4066: 4065:compositional 4061: 4059: 4058:partial order 4051: 4046: 4043: 4040: 4037: 4034: 4030: 4027: 4025: 4022: 4020: 4017: 4015: 4012: 4011: 4010: 4005: 3997: 3993: 3989: 3988: 3987: 3985: 3974: 3971: 3967: 3963: 3959: 3955: 3954: 3953: 3951: 3940: 3937: 3930: 3927: 3923: 3919: 3918: 3917: 3915: 3911: 3907: 3906:homeomorphism 3903: 3899: 3888: 3884: 3877: 3874: 3870: 3866: 3865: 3864: 3862: 3857: 3849: 3845: 3841: 3840: 3839: 3836: 3831: 3829: 3821: 3817: 3816: 3815: 3813: 3809: 3805: 3801: 3797: 3789: 3787: 3785: 3777: 3772: 3770: 3768: 3767:shortest path 3764: 3760: 3756: 3752: 3748: 3744: 3743:degree matrix 3740: 3736: 3731: 3729: 3725: 3720: 3717: 3713: 3712:sparse graphs 3708: 3704: 3698: 3690: 3688: 3686: 3682: 3678: 3673: 3671: 3667: 3662: 3660: 3655: 3651: 3646: 3645:Graph drawing 3638: 3636: 3629: 3627: 3625: 3624: 3619: 3615: 3610: 3608: 3604: 3600: 3596: 3592: 3588: 3584: 3580: 3576: 3571: 3569: 3565: 3561: 3557: 3552: 3548: 3547:Kenneth Appel 3544: 3539: 3537: 3536: 3531: 3527: 3523: 3519: 3515: 3511: 3507: 3503: 3499: 3495: 3491: 3488:addressed to 3487: 3483: 3479: 3474: 3472: 3468: 3464: 3456: 3452: 3448: 3444: 3440: 3439: 3438: 3436: 3435: 3430: 3425: 3422: 3418: 3414: 3410: 3406: 3405: 3400: 3396: 3392: 3388: 3383: 3381: 3377: 3373: 3369: 3366:initiated by 3365: 3361: 3359: 3354: 3350: 3346: 3337: 3330: 3328: 3326: 3318: 3316: 3314: 3310: 3306: 3298: 3296: 3294: 3289: 3286: 3282: 3278: 3274: 3269: 3266: 3258: 3256: 3253: 3249: 3245: 3241: 3233: 3230: 3225: 3218: 3216: 3214: 3209: 3205: 3201: 3196: 3192: 3188: 3184: 3180: 3176: 3172: 3168: 3164: 3160: 3152: 3150: 3148: 3144: 3140: 3136: 3132: 3129:, which uses 3128: 3124: 3120: 3116: 3112: 3108: 3104: 3100: 3096: 3092: 3084: 3082: 3080: 3076: 3072: 3068: 3064: 3060: 3056: 3052: 3047: 3043: 3038: 3034: 3026: 3024: 3022: 3017: 3007: 3000: 2998: 2984: 2964: 2956: 2940: 2920: 2897: 2894: 2891: 2868: 2860: 2844: 2836: 2820: 2811: 2809: 2808: 2803: 2799: 2782: 2776: 2772: 2768: 2762: 2759: 2756: 2750: 2744: 2741: 2738: 2731: 2724: 2721: 2718: 2698: 2677: 2671: 2667: 2663: 2657: 2654: 2651: 2645: 2639: 2636: 2633: 2626: 2622: 2619: 2599: 2578: 2574: 2571: 2568: 2554: 2550: 2546: 2540: 2537: 2534: 2528: 2522: 2519: 2516: 2509: 2485: 2482: 2479: 2456: 2448: 2447: 2441: 2439: 2431: 2427: 2410: 2406: 2403: 2400: 2386: 2382: 2378: 2372: 2369: 2366: 2360: 2354: 2351: 2348: 2341: 2334: 2331: 2328: 2321: 2318: 2314: 2310: 2306: 2302: 2299:(also called 2298: 2294: 2278: 2271: 2268: 2264: 2261:(also called 2260: 2256: 2240: 2233: 2232: 2231: 2214: 2211: 2208: 2205: 2202: 2196: 2193: 2185: 2180: 2178: 2177: 2157: 2154: 2151: 2140: 2139:inverted edge 2121: 2118: 2115: 2092: 2072: 2064: 2048: 2028: 2021: 2017: 2001: 1993: 1977: 1970:of the edge, 1969: 1953: 1933: 1913: 1893: 1870: 1867: 1864: 1852: 1838: 1818: 1815: 1807: 1785: 1781: 1772: 1764: 1763:ordered pairs 1760: 1756: 1752: 1748: 1744: 1741:(also called 1740: 1736: 1719: 1715: 1712: 1709: 1695: 1691: 1687: 1681: 1678: 1675: 1669: 1663: 1660: 1657: 1650: 1646: 1643: 1636: 1633: 1629: 1626:(also called 1625: 1621: 1605: 1598: 1597: 1596: 1579: 1576: 1573: 1567: 1564: 1556: 1551: 1549: 1545: 1536: 1531: 1523: 1521: 1507: 1504: 1501: 1493: 1477: 1457: 1434: 1431: 1428: 1405: 1397: 1381: 1361: 1354: 1338: 1329: 1316: 1312: 1302: 1297: 1292: 1290: 1286: 1282: 1261: 1248: 1227: 1214: 1198: 1178: 1170: 1169:infinite case 1154: 1134: 1126: 1124: 1123: 1117: 1113: 1094: 1091: 1088: 1085: 1082: 1079: 1073: 1070: 1067: 1055: 1052: 1049: 1029: 1006: 1003: 1000: 997: 994: 991: 985: 982: 979: 970: 967: 947: 924: 921: 918: 906: 903: 900: 897: 894: 891: 885: 882: 879: 850: 844: 838: 835: 832: 809: 801: 800: 794: 792: 791: 781: 777: 758: 755: 752: 740: 737: 734: 731: 728: 725: 719: 716: 713: 701: 698: 695: 688: 685: 681: 678:(also called 677: 673: 657: 650: 647: 643: 640:(also called 639: 635: 619: 612: 611: 610: 593: 590: 587: 584: 581: 575: 572: 564: 545: 533: 520: 516: 514: 513: 496: 476: 468: 452: 432: 425: 421: 405: 385: 362: 359: 356: 344: 342: 334: 331:), which are 330: 326: 323:(also called 322: 318: 299: 296: 293: 281: 278: 275: 272: 269: 266: 260: 257: 254: 245: 242: 235: 232: 228: 225:(also called 224: 220: 204: 197: 196: 195: 178: 175: 172: 166: 163: 156: 152: 143: 136: 134: 132: 126: 118: 116: 114: 110: 106: 102: 98: 94: 91:(also called 90: 89: 84: 80: 77:(also called 76: 75: 70: 66: 65: 60: 56: 48: 43: 34: 30: 19: 8024:Graph theory 7826:Cyberwarfare 7485:Cryptography 6871: 6859: 6847: 6828: 6761:Optimization 6623:Differential 6547:Differential 6514:Order theory 6509:Graph theory 6508: 6413:Group theory 6220:Online books 6156: 6126: 6116: 6103: 6094: 6086:Graph Theory 6085: 6072: 6059: 6029: 6007: 5996: 5980:. Springer. 5978:Graph Theory 5977: 5968: 5957: 5947: 5917: 5910: 5891: 5887: 5881: 5862: 5858: 5852: 5833: 5829: 5816: 5807: 5797:, retrieved 5790:the original 5781: 5771: 5762: 5753: 5743:, retrieved 5729:Graph Theory 5728: 5718: 5694:(432): 284. 5691: 5687: 5677: 5660: 5656: 5646: 5620: 5614: 5599: 5590: 5586: 5580: 5569: 5563: 5553: 5546: 5503: 5499: 5489: 5436: 5432: 5419: 5400: 5394: 5386: 5377: 5366:. Retrieved 5359:the original 5350: 5343: 5310: 5306: 5300: 5289: 5281: 5248: 5244: 5238: 5205: 5201: 5195: 5168: 5164: 5151: 5126: 5122: 5110: 5067: 5063: 5053: 5010: 5006: 5000: 4947: 4941: 4917: 4905: 4897: 4892: 4880: 4861:Tutte, W. T. 4796:Kőnig, Dénes 4667:Group theory 4267: 4225: 4218: 4211: 4205: 4201: 4198: 4162: 4131: 4128:Network flow 4111:Steiner tree 4062: 4055: 4007: 3983: 3981: 3972: 3947: 3938: 3928: 3895: 3886: 3875: 3853: 3832: 3825: 3807: 3793: 3781: 3732: 3721: 3700: 3674: 3670:planar graph 3663: 3656: 3652: 3648: 3633: 3621: 3611: 3572: 3540: 3533: 3517: 3475: 3467:Frank Harary 3460: 3454: 3450: 3442: 3432: 3426: 3402: 3384: 3363: 3356: 3342: 3322: 3319:Other topics 3313:group theory 3302: 3293:connectomics 3290: 3270: 3262: 3237: 3211:studied via 3200:porous media 3156: 3109:, which are 3088: 3030: 3015: 3012: 3001:Applications 2954: 2858: 2812: 2805: 2801: 2797: 2444: 2442: 2437: 2435: 2430:ordered pair 2425: 2316: 2312: 2308: 2304: 2300: 2296: 2266: 2262: 2258: 2230:comprising: 2183: 2181: 2174: 2138: 2062: 2019: 2015: 1991: 1967: 1854:In the edge 1853: 1770: 1768: 1761:) which are 1758: 1754: 1750: 1746: 1742: 1738: 1631: 1627: 1623: 1595:comprising: 1554: 1552: 1547: 1543: 1541: 1491: 1395: 1330: 1314: 1310: 1300: 1295: 1293: 1288: 1284: 1280: 1246: 1212: 1171:. 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Index

Graph-theoretic
Graph of a function
Graph (disambiguation)

drawing
mathematics
graphs
mathematical structures
vertices
edges
discrete mathematics
Glossary of graph theory
mathematical structures

ordered pair
set
set
unordered pairs
multiple edges



set
set
unordered pair
multigraph
loop
pseudograph
infinite case
homogeneous relation

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