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There are 28 six-vertex cycles in the
Heawood graph. Each 6-cycle is disjoint from exactly three other 6-cycles; among these three 6-cycles, each one is the symmetric difference of the other two. The graph with one node per 6-cycle, and one edge for each disjoint pair of 6-cycles, is the
293:. For instance, the figure shows the vertices of the graph placed on a cycle, with the internal diagonals of the cycle forming a matching. By subdividing the cycle edges into two matchings, we can partition the Heawood graph into three perfect matchings (that is,
484:: it can be embedded in the plane such that adjacent vertices are exactly at distance one apart, with no two vertices embedded to the same point and no vertex embedded into a point within an edge.
608:
430:, the graph representing incidences between points and lines in that geometry. With this interpretation, the 6-cycles in the Heawood graph correspond to
297:) in eight different ways. Every two perfect matchings, and every two Hamiltonian cycles, can be transformed into each other by a symmetry of the graph.
1012:
776:
464:
685:
504:(7), a group of order 336. It acts transitively on the vertices, on the edges and on the arcs of the graph. Therefore, the Heawood graph is a
1082:
774:
Abreu, M.; Aldred, R. E. L.; Funk, M.; Jackson, Bill; Labbate, D.; Sheehan, J. (2004), "Graphs and digraphs with all 2-factors isomorphic",
222:
471:
508:. It has automorphisms that take any vertex to any other vertex and any edge to any other edge. More strongly, the Heawood graph is
1096:
865:
692:
1152:
898:
861:
627:
454:
262:, and all cycles in the graph have six or more edges. Every smaller cubic graph has shorter cycles, so this graph is the 6-
675:
636:
1170:
and Dobcsányi, P. "Trivalent
Symmetric Graphs Up to 768 Vertices." J. Combin. Math. Combin. Comput. 40, 41-63, 2002.
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in 1890, who proved that no map on the torus could require more than seven colors and thus this map is maximal.
701:
978:
651:
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1204:
497:
120:
94:
84:
610:. It is the only graph with this characteristic polynomial, making it a graph determined by its spectrum.
279:
201:
764:
Additions and
Corrections to the book Distance-Regular Graphs (Brouwer, Cohen, Neumaier; Springer; 1989)
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57:
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1088:
467:). Including the Heawood graph, there are 8 distinct graphs of order 14 with crossing number 3.
1092:
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729:
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209:
1021:
915:
880:
832:
785:
657:
516:, the Heawood graph, referenced as F014A, is the only cubic symmetric graph on 14 vertices.
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in the
Heawood graph; for each matching, the set of edges not in the matching forms a
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Heawood's map. Opposite edges of the large hexagon are connected to form a torus.
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faces. Each face of the map is adjacent to every other face, thus as a result
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3, and is the smallest cubic graph with that crossing number (sequence
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813:
Dejter, Italo J. (2011), "From the
Coxeter graph to the Klein graph",
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the map requires 7 colors. The map and graph were discovered by
1125:"Classification of Trivalent Symmetric Graphs of Small Order"
459:
540:
1043:
Eleven unit distance embeddings of the
Heawood graph
470:The Heawood graph is the smallest cubic graph with
181:
171:
161:
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93:
83:
73:
63:
53:
39:
602:
434:in the Fano plane. Also, the Heawood graph is the
31:, a graph family that contains the Heawood graph.
1183:. Master Thesis, University of Tübingen, 2018
1150:"Cubic Symmetric Graphs (The Foster Census)."
873:Bulletin of the American Mathematical Society
866:"Self-dual configurations and regular graphs"
8:
1005:"Graphs and obstructions in four dimensions"
366:such that every pair of faces is adjacent.
362:, the only known polyhedron apart from the
246:with 14 vertices and 21 edges, named after
1123:Conder, Marston; Morton, Margaret (1995).
496:of the Heawood graph is isomorphic to the
358:The map can be faithfully realized as the
1050:
1025:
1013:Journal of Combinatorial Theory, Series B
856:
854:
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789:
777:Journal of Combinatorial Theory, Series B
751:
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539:
720:
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603:{\displaystyle (x-3)(x+3)(x^{2}-2)^{6}}
36:
1132:Australasian Journal of Combinatorics
7:
309:Geometric and topological properties
1181:Engineering Linear Layouts with SAT
1087:. New York: North Holland. p.
1041:Gerbracht, Eberhard H.-A. (2009),
25:
472:Colin de Verdière graph invariant
34:Undirected graph with 14 vertices
960:Quarterly Journal of Mathematics
700:
684:
665:
650:
635:
620:
393:
382:
373:
45:
885:10.1090/S0002-9904-1950-09407-5
406:and two representations of its
1084:Graph Theory with Applications
958:(1890). "Map-colour theorem".
591:
571:
568:
556:
553:
541:
266:, the smallest cubic graph of
223:Table of graphs and parameters
1:
691:embedded in a torus (compare
27:Not to be confused with the
1003:Hein van der Holst (2006).
899:"The many names of (7,3,1)"
1221:
1027:10.1016/j.jctb.2005.09.004
791:10.1016/j.jctb.2004.09.004
26:
532:characteristic polynomial
422:The Heawood graph is the
329:without crossings onto a
272:distance-transitive graph
221:
44:
977:Szilassi, Lajos (1986),
534:of the Heawood graph is
254:Combinatorial properties
815:Journal of Graph Theory
498:projective linear group
480:The Heawood graph is a
321:The Heawood graph is a
604:
453:The Heawood graph has
318:
605:
325:; that is, it can be
316:
907:Mathematics Magazine
897:Brown, Ezra (2002).
672:embedded in a torus
538:
488:Algebraic properties
333:. The result is the
1061:2009arXiv0912.5395G
986:Structural Topology
757:Brouwer, Andries E.
708:Szilassi polyhedron
512:. According to the
482:unit distance graph
360:Szilassi polyhedron
198:Distance-transitive
1155:2008-07-20 at the
730:Weisstein, Eric W.
600:
494:automorphism group
353:Percy John Heawood
319:
248:Percy John Heawood
58:Percy John Heawood
1200:Individual graphs
979:"Regular toroids"
837:10.1002/jgt.20597
679:
676:shown as a square
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295:3-color its edges
291:Hamiltonian cycle
287:perfect matchings
228:
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217:Orientably simple
16:(Redirected from
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1101:. Archived from
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962:. First Series.
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930:. Archived from
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510:4-arc-transitive
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280:distance regular
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244:undirected graph
202:Distance-regular
133:Chromatic number
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760:"Heawood graph"
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733:"Heawood Graph"
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643:chromatic index
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1179:Jessica Wolz,
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1020:(3): 388–404.
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956:Heawood, P. J.
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1105:on 2010-04-13
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514:Foster census
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438:of the group
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436:Tits building
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303:Coxeter graph
298:
296:
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285:There are 24
283:
281:
277:
276:Foster census
273:
269:
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261:
258:The graph is
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240:Heawood graph
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115:Automorphisms
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40:Heawood graph
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1107:. Retrieved
1103:the original
1083:
1075:Bondy, J. A.
1069:
1042:
1036:
1017:
1011:
998:
989:
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939:. Retrieved
932:the original
914:(2): 83–94.
911:
905:
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775:
769:
736:
723:
529:
525:queue number
518:
491:
479:
469:
452:
421:
411:(below as a
357:
320:
299:
284:
257:
239:
236:graph theory
232:mathematical
229:
173:Queue number
364:tetrahedron
335:regular map
270:6. It is a
210:Hamiltonian
54:Named after
18:Heawood map
1194:Categories
1168:Conder, M.
1148:Royle, G.
1109:2019-12-18
966:: 322–339.
941:2006-10-27
715:References
428:Fano plane
424:Levi graph
408:Levi graph
404:Fano plane
182:Properties
1052:0912.5395
828:1002.1960
738:MathWorld
585:−
548:−
432:triangles
345:hexagonal
343:, with 7
274:(see the
234:field of
214:Symmetric
186:Bipartite
1153:Archived
1081:(1976).
864:(1950),
349:coloring
327:embedded
206:Toroidal
95:Diameter
65:Vertices
1057:Bibcode
992:: 69–80
928:3219140
862:Coxeter
821:: 1–9,
800:2099150
614:Gallery
519:It has
463:in the
460:A110507
426:of the
230:In the
1138:: 146.
1095:
926:
845:754481
843:
798:
523:3 and
242:is an
238:, the
85:Radius
1128:(PDF)
1047:arXiv
1008:(PDF)
982:(PDF)
935:(PDF)
924:JSTOR
902:(PDF)
869:(PDF)
841:S2CID
823:arXiv
693:video
475:μ = 6
338:{6,3}
331:torus
268:girth
260:cubic
190:Cubic
153:Genus
119:336 (
105:Girth
75:Edges
1093:ISBN
530:The
492:The
465:OEIS
264:cage
194:Cage
1089:237
1022:doi
916:doi
881:doi
833:doi
786:doi
527:2.
500:PGL
340:2,1
125:(7)
121:PGL
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