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No-three-in-line problem

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2055:, crossings between pairs of edges are unavoidable, but one should still avoid placements that cause a vertex to lie on an edge through two other vertices. When the vertices are placed with no three in line, this kind of problematic placement cannot occur, because the entire line through any two vertices, and not just the line segment, is free of other vertices. The fact that the no-three-in-line problem has a solution with linearly many points can be translated into graph drawing terms as meaning that every graph, even a 765: 22: 419: 412: 405: 398: 391: 384: 377: 370: 363: 356: 349: 342: 335: 328: 321: 314: 308: 3015:. Just as the original no-three-in-line problem can be used for two-dimensional graph drawing, one can use this three-dimensional solution to draw graphs in the three-dimensional grid. Here the non-collinearity condition means that a vertex should not lie on a non-adjacent edge, but it is normal to work with the stronger requirement that no two edges cross. 3026:, sets of integers with no three forming an arithmetic progression. However, it does not work well to use this same idea of choosing points near a circle in two dimensions: this method finds points forming convex polygons, which satisfy the requirement of having no three in line, but are too small. The largest convex polygons with vertices in an 3173:
in which the left side of the torus is connected to the right side, and the top side is connected to the bottom side. This has the effect, on slanted lines through the grid, of connecting them up into longer lines through more points, and therefore making it more difficult to select points with at
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This application was the motivation for Paul Erdős to find his solution for the no-three-in-line problem. It remained the best area lower bound known for the Heilbronn triangle problem from 1951 until 1982, when it was improved by a logarithmic factor using a construction that was not based on the
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points, anywhere in a unit square, not restricted to a grid. The goal of the placement is to avoid small-area triangles, and more specifically to maximize the area of the smallest triangle formed by three of the points. For instance, a placement with three points in line would be very bad by this
2059:, can be drawn without unwanted vertex-edge incidences using a grid whose area is quadratic in the number of vertices, and that for complete graphs no such drawing with less than quadratic area is possible. The complete graphs also require a linear number of colors in any 2324:. In this terminology, the no-three-in-line problem seeks the largest subset of a grid that is in general position, but researchers have also considered the problem of finding the largest general position subset of other non-grid sets of points. It is 2254:
half of a grid square. Therefore, solving an instance of the no-three-in-line problem and then scaling down the integer grid to fit within a unit square produces solutions to the Heilbronn triangle problem where the smallest triangle has area
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When both dimensions are equal, and prime, it is not possible to place exactly one point in each row and column without forming a linear number of collinear triples. Higher-dimensional torus versions of the problem have also been studied.
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most two from each line. These extended lines can also be interpreted as normal lines through an infinite grid in the Euclidean plane, taken modulo the dimensions of the torus. For a torus based on an
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After an error in the heuristic reasoning leading to this conjecture was uncovered, Guy corrected the error and made the stronger conjecture that one cannot do more than sublinearly better than
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that tries to solve the no-three-in-line problem by placing points one at a time until it gets stuck. If only axis-parallel and diagonal lines are considered, then every such set has at least
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points can be placed in grids of large size. Known methods can place linearly many points in grids of arbitrary size, but the best of these methods place slightly fewer than
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Misiak, Aleksander; Stępień, Zofia; Szymaszkiewicz, Alicja; Szymaszkiewicz, Lucjan; Zwierzchowski, Maciej (2016). "A note on the no-three-in-line problem on a torus".
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The example of the grid shows that this bound cannot be significantly improved. The proof of existence of these large general-position subsets can be converted into a
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criterion, because these three points would form a degenerate triangle with area zero. On the other hand, if the points can be placed on a grid of side length
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on the number of points that can be placed. More precisely, they conjectured that the number of points that can be placed is at most a sublinear amount larger
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Several related problems of finding points with no three in line, among other sets of points than grids, have also been studied. Although originating in
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In a later version of the puzzle, Dudeney modified the problem, making its solution unique, by asking for a solution in which two of the pawns are on
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Solution to Dudeney's puzzle of placing 16 pawns on a chessboard such that no three pawns lie on the same line, with two pawns on squares d4 and e5.
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Adena, Michael A.; Holton, Derek A.; Kelly, Patrick A. (1974). "Some thoughts on the no-three-in-line problem". In Holton, Derek A. (ed.).
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points. However, less is known about the version of the problem where all lines are considered: every greedy placement includes at least
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in 1900. Brass, Moser, and Pach call it "one of the oldest and most extensively studied geometric questions concerning lattice points".
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Cooper, Alec S.; Pikhurko, Oleg; Schmitt, John R.; Warrington, Gregory S. (2014). "Martin Gardner's minimum no-3-in-a-line problem".
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Di Giacomo, Emilio; Liotta, Giuseppe; Meijer, Henk (2005). "Computing straight-line 3d grid drawings of graphs in linear volume".
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One can get a finer-grained understanding of the running time of algorithms for finding the exact optimal solution by using
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problem concerns a similar problem to the no-three-in-line problem in spaces that are both high-dimensional, and based as
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its size to within a constant factor; this hardness of approximation result is summarized by saying that the problem is
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Brass, Peter; Cenek, Eowyn; Duncan, Christian A.; Efrat, Alon; Erten, Cesim; Ismailescu, Dan P.; Kobourov, Stephen G.;
4262:(October 1976). "Combinatorial problems, some old, some new and all newly attacked by computer". Mathematical Games. 4820: 4760: 4685: 4047: 2167: 473: 289: 4396: 4052: 2500: 2400:
that simply chooses points one at a time until all remaining points lie on lines through pairs of chosen points.
2404: 2032: 281: 4739: 4906: 3907: 2329: 2063:, but other graphs that can be colored with fewer colors can also be drawn on smaller grids: if a graph has 1706: 733:
is not known. However, both proven and conjectured bounds limit this number to within a range proportional
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Combinatorial Mathematics: Proceedings of the Second Australian Conference (University of Melbourne, 1973)
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Another generalization to higher dimensions is to find as many points as possible in a three dimensional
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In much higher dimensions, sets of grid points with no three in line, obtained by choosing points near a
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onto the board so that no three are in a line. This is exactly the no-three-in-line problem, for the
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grid such that no four of them are in the same plane. This sequence begins 5, 8, 10, 13, 16, ...
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The Art of Computer Programming, Fascicle 1b: A Draft of Section 7.1.4: Binary Decision Diagrams
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The no-three-in-line problem also has applications to another problem in discrete geometry, the
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in 1900, as a puzzle in recreational mathematics, phrased in terms of placing the 16 pawns of a
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has three in a line. Equivalently, this is the smallest set that could be produced by a
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grid, the maximum number of points that can be chosen with no three in line is at most
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grid so that no three points lie on the same line. The problem concerns lines of all
4652: 4251: 3946: 4765: 4727: 4663:; Thiele, Torsten; Tóth, Géza (1998). "Three-dimensional grid drawings of graphs". 4605: 4556: 4083: 3105: 3101: 2048: 1116: 3886: 2134:
The no-three-in-line drawing of a complete graph is a special case of this result
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grid that cannot be extended: it has no three points in a line, but every proper
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Solutions to the no-three-in-line problem can be used to avoid certain kinds of
1872: 4812: 4636: 3685:"Geometric dominating sets – a minimum version of the No-Three-In-Line Problem" 2910:
Similarly to Erdős's 2D construction, this can be accomplished by using points
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Another variation on the problem involves converting the grid into a discrete
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Non-collinear sets of points in the three-dimensional grid were considered by
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of size matching the existence bound, using an algorithmic technique known as
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some three of them would all lie on the same horizontal line of the grid. For
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1, 2, 11, 32, 50, 132, 380, 368, 1135, 1120, 4348, 3622, 10568, ... (sequence
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it can be found in an amount of time that is an exponential function of
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Many authors have published solutions to this problem for small values
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Ku, Cheng Yeaw; Wong, Kok Bin (2018). "On no-three-in-line problem on
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of a given graph at integer coordinates in the plane, and drawing the
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points in a grid would include a row of three or more points, by the
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A set of 20 points in a 10 × 10 grid, with no three points in a line.
3423:. The discovery of this error was credited by Pegg to Gabor Ellmann. 691:
1, 1, 4, 5, 11, 22, 57, 51, 156, 158, 566, 499, 1366, ... (sequence
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conjectured that for large grids, there is a significantly smaller
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International Journal of Computational Geometry & Applications
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points before getting stuck, but nothing better than the trivial
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there exist general-position subsets of size nearly proportional
4357:. Proceedings of the Oberwolfach Meeting “Kombinatorik” (1986). 3495: 2320:, finite sets of points with no three in line are said to be in 4483:
Kløve, Torleiv (1979). "On the no-three-in-line problem. III".
4391: 3522: 3658:. Lecture Notes in Mathematics. Vol. 403. pp. 6–17. 1953:{\displaystyle c={\sqrt{\frac {2\pi ^{2}}{3}}}\approx 1.874.} 709:
The exact number of points that can be placed, as a function
67:, not only those aligned with the grid. It was introduced by 4688:(2013). "On the general position subset selection problem". 4321:
Hall, R. R.; Jackson, T. H.; Sudbery, A.; Wild, K. (1975).
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to find this subset, for certain input sets, and hard to
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within the unit square, with no three in a line, then by
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colors, it can be drawn in a grid with area proportional
2017:{\displaystyle c={\frac {\pi }{\sqrt {3}}}\approx 1.814.} 3534: 3479: 3477: 3345: 2838:. They proved that the maximum number of points in the 1052: 3566: 3395: 3382:
Erdős did not publish this observation; it appears in
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is not prime, one can perform this construction for a
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and some larger values. The numbers of solutions with
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The numbers of equivalence classes of solutions with
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points, by placing points in multiple copies of the
4093:"An improved construction of progression-free sets" 3816:"Section 10.1: Packing lattice points in subspaces" 1674:one can perform this construction for a prime near 1622:may be chosen arbitrarily as long as it is nonzero 814:grid, using the method of Erdős. The largest prime 476:, attacking each other in the center of the board. 284:, the no-three-in-line problem has applications in 3329: 3231: 3192: 3135: 3088: 3044: 3003: 2981: 2958: 2900: 2862: 2818: 2795: 2751: 2717: 2669: 2641: 2588: 2538: 2518: 2489: 2475:with the exponent of the polynomial not depending 2465: 2443: 2421: 2388: 2350: 2292: 2244: 2203: 2182: 2154: 2124: 2099: 2075: 2016: 1975: 1952: 1892: 1859: 1828: 1796: 1774: 1742: 1694: 1666: 1644: 1614: 1592: 1563: 1531: 1488: 1453: 1427: 1390: 1368: 1342: 1320: 1300: 1274: 1248: 1226: 1191: 1168: 1131: 1107: 1074: 1054: 1037: 998: 964: 915: 892: 853: 826: 806: 780: 747: 723: 680: 639: 611: 591: 564: 544: 518: 493: 462: 268: 243: 212: 187: 165: 145: 118: 89: 55: 4525:(1982). "A lower bound for Heilbronn's problem". 4208:Froese, Vincent; Kanj, Iyad; Nichterlein, André; 3562: 2499:Problems with this kind of time bound are called 2039:. The problem they apply to involves placing the 3211: 2692: 2655:algorithm for finding a general-position subset 301: 4834:Computational Geometry: Theory and Applications 4394:[On the grid points on convex curves]. 4323:"Some advances in the no-three-in-line problem" 4268:. Vol. 235, no. 4. pp. 131–137. 4019:Computational Geometry: Theory and Applications 4212:(2017). "Finding points in general position". 4181:"Progress in the no-three-in-line problem, II" 3625: 3558: 3270: 4355:"No-three-in-line for seventeen and nineteen" 4353:; Oertel, Philipp; Prellberg, Thomas (1989). 4145:. Cambridge University Press. pp. 72–86. 4143:Forbidden Configurations in Discrete Geometry 1464:Erdős' bound has been improved subsequently: 8: 4435:"Simple Set Game Proof Stuns Mathematicians" 1806:For, if more points are placed, then by the 1356:is much smaller than the primes themselves, 4392:"Über die Gitterpunkte auf konvexen Kurven" 3370: 3366: 3353: 3349: 1836:, this trivial bound is known to be tight. 688:points under reflections and rotations are 4800:Journal of the London Mathematical Society 4528:Journal of the London Mathematical Society 4152:"Progress in the no-three-in-line problem" 863:the solution places points at coordinates 130:. Although the problem can be solved with 37:asks how many points can be placed in the 4846: 4701: 4674: 4626: 4465: 4372: 4340: 4303: 4225: 4198: 4169: 4120: 4110: 4065: 3973: 3920: 3860: 3792: 3775:"On simultaneous planar graph embeddings" 3747: 3710: 3700: 3601: 3510: 3285:, April 29 and May 13, 1900, as cited by 3206: 3179: 3116: 3073: 3069: 3057: 3031: 2996: 2971: 2950: 2937: 2916: 2889: 2877: 2843: 2808: 2780: 2776: 2764: 2738: 2704: 2662: 2629: 2621: 2619: 2605: 2576: 2568: 2566: 2552: 2531: 2511: 2482: 2458: 2436: 2414: 2376: 2368: 2343: 2281: 2272: 2261: 2234: 2228: 2222: 2196: 2175: 2141: 2114: 2092: 2068: 1996: 1988: 1965: 1937: 1926: 1915: 1907: 1882: 1849: 1815: 1789: 1764: 1710: 1708: 1684: 1679: 1659: 1634: 1629: 1607: 1582: 1577: 1547: 1521: 1501: 1496:is prime, one can obtain a solution with 1478: 1473: 1440: 1405: 1383: 1361: 1335: 1313: 1287: 1261: 1241: 1236:contains no three collinear points. When 1207: 1181: 1160: 1145: 1124: 1100: 1067: 1051: 1017: 1011: 979: 930: 905: 884: 869: 840: 819: 793: 773: 740: 716: 670: 626: 604: 581: 557: 531: 508: 486: 449: 258: 233: 225: 202: 180: 158: 135: 102: 79: 42: 3822:. Springer, New York. pp. 417–421. 3730:"Update on the no-three-in-line problem" 3535:Aichholzer, Eppstein & Hainzl (2023) 3499: 3483: 3407: 3341: 2451:multiplied by a polynomial in the input 1868: 1095:, is based on the observation that when 4141:(2018). "Chapter 9: General position". 3546: 3317: 3305: 3263: 2835: 3820:Research Problems in Discrete Geometry 3637: 3589: 1782:points may be placed in a grid of any 4797:(1951). "On a problem of Heilbronn". 4746:. Mathematical Association of America 4666:Graph Drawing, 5th Int. Symp., GD '97 4448:"On the no-three-in-line problem. II" 4008:. Originally published in the London 3954:Craggs, D.; Hughes-Jones, R. (1976). 3577: 3346:Harborth, Oertel & Prellberg 1989 3337: 3333: 3286: 1867:points can be placed on small grids, 1743:{\displaystyle {\tfrac {3}{2}}n-o(n)} 1461:grid with no three points collinear. 552:grid with no three in a line for all 418: 411: 404: 397: 390: 383: 376: 369: 362: 355: 348: 341: 334: 327: 320: 313: 304: 7: 4690:SIAM Journal on Discrete Mathematics 3879:10.4169/amer.math.monthly.121.03.213 3871:10.4169/amer.math.monthly.121.03.213 3683:; Hainzl, Eva-Maria (January 2023). 3567:Di Giacomo, Liotta & Meijer 2005 3456: 3444: 3420: 3383: 2870:grid with no three points collinear 2699:asked for the smallest subset of an 1400:so this method can be used to place 1092: 3022:, have been used for finding large 2642:{\textstyle \ell =O({\sqrt {|S|}})} 2589:{\textstyle \ell =O({\sqrt {|S|}})} 4763:(2007). "No-three-in-line-in-3D". 3900:"Collinear points in permutations" 3469:Komlós, Pintz & Szemerédi 1982 2879: 2766: 2263: 2245:{\displaystyle \varepsilon ^{2}/2} 2215:every triangle would have area at 2170:. In this problem, one must place 2051:. For certain graphs, such as the 197:it is conjectured that fewer than 14: 4433:Klarreich, Erica (May 31, 2016). 3956:"On the no-three-in-line problem" 3136:{\displaystyle N\times N\times N} 2863:{\displaystyle n\times n\times n} 2360:a solution with the non-constant 4002:. Edinburgh: Nelson. p. 94. 2959:{\displaystyle (x,y,x^{2}+y^{2}} 2796:{\displaystyle \Omega (n^{2/3})} 2693:Adena, Holton & Kelly (1974) 2293:{\displaystyle \Omega (1/n^{2})} 1328:is the largest prime that is at 417: 410: 403: 396: 389: 382: 375: 368: 361: 354: 347: 340: 333: 326: 319: 312: 306: 4486:Journal of Combinatorial Theory 4453:Journal of Combinatorial Theory 4328:Journal of Combinatorial Theory 4186:Journal of Combinatorial Theory 4157:Journal of Combinatorial Theory 3961:Journal of Combinatorial Theory 3735:Journal of Combinatorial Theory 3563:Dujmović, Morin & Wood 2005 3108:rather than over the integers. 1038:{\displaystyle 4^{2}=16\cong 5} 965:{\displaystyle i=0,1,\dots p-1} 434:The problem was first posed by 18:Geometry problem on grid points 4866:"The No-Three-in-Line Problem" 4291:Canadian Mathematical Bulletin 4286:"The no-three-in-line problem" 3810:Brass, Peter; Moser, William; 3728:Anderson, David Brent (1979). 3330:Craggs & Hughes-Jones 1976 3226: 3214: 3083: 3062: 2976: 2918: 2901:{\displaystyle \Theta (n^{2})} 2895: 2882: 2790: 2769: 2636: 2630: 2622: 2616: 2583: 2577: 2569: 2563: 2389:{\displaystyle O({\sqrt {k}})} 2383: 2373: 2307:Generalizations and variations 2287: 2266: 1737: 1731: 1518: 1506: 1422: 1416: 1354:gap between consecutive primes 1186: 1147: 993: 981: 910: 871: 503:and by 1998 it was known that 97:points can be placed, because 1: 4098:Israel Journal of Mathematics 3848:American Mathematical Monthly 526:points could be placed on an 4878:"No-Three-in-a-Line-Problem" 4848:10.1016/j.comgeo.2004.06.001 4499:10.1016/0097-3165(79)90055-4 4467:10.1016/0097-3165(78)90053-5 4374:10.1016/0012-365X(88)90135-5 4342:10.1016/0097-3165(75)90043-6 4171:10.1016/0097-3165(92)90012-J 4032:10.1016/j.comgeo.2004.11.003 3975:10.1016/0097-3165(76)90030-3 3794:10.1016/j.comgeo.2006.05.006 3749:10.1016/0097-3165(79)90025-6 3712:10.1016/j.comgeo.2022.101913 3559:Pach, Thiele & Tóth 1998 3271:Brass, Moser & Pach 2005 3171:periodic boundary conditions 2336:. If the largest subset has 2204:{\displaystyle \varepsilon } 1227:{\displaystyle 0\leq i<n} 4179:Flammenkamp, Achim (1998). 4150:Flammenkamp, Achim (1992). 834:less than the grid size is 807:{\displaystyle 12\times 12} 599:points for small values of 4933: 4637:10.1016/j.disc.2015.08.006 3996:"317. A puzzle with pawns" 3626:Cooper & Solymosi 2005 3232:{\displaystyle 2\gcd(m,n)} 3089:{\displaystyle O(n^{2/3})} 2691:Repeating a suggestion of 2303:no-three-in-line problem. 2168:Heilbronn triangle problem 1702:to obtain a solution with 290:Heilbronn triangle problem 4779:10.1007/s00453-006-0158-9 4590:10.1007/s00373-018-1878-8 4397:Mathematische Zeitschrift 4236:10.1142/S021819591750008X 4122:10.1007/s11856-011-0061-1 4076:10.1137/S0097539702416141 4053:SIAM Journal on Computing 4000:Amusements in Mathematics 3931:10.1007/s00026-005-0248-4 3193:{\displaystyle m\times n} 3045:{\displaystyle n\times n} 2718:{\displaystyle n\times n} 2501:fixed-parameter tractable 2047:of the graph as straight 1454:{\displaystyle n\times n} 1301:{\displaystyle n\times n} 1275:{\displaystyle p\times p} 760:General placement methods 545:{\displaystyle n\times n} 56:{\displaystyle n\times n} 4813:10.1112/jlms/s1-26.3.198 4676:10.1007/3-540-63938-1_49 4578:Graphs and Combinatorics 4561:"Answer to exercise 242" 4390:Jarník, Vojtěch (1926). 3011:is a prime congruent to 2405:parameterized complexity 2312:General-position subsets 1829:{\displaystyle n\leq 46} 1532:{\displaystyle 3(n-2)/2} 1169:{\displaystyle (i,i^{2}} 893:{\displaystyle (i,i^{2}} 768:Suboptimal placement of 282:recreational mathematics 31:no-three-in-line problem 4541:10.1112/jlms/s2-25.1.13 4446:Kløve, Torleiv (1978). 4284:; Kelly, P. A. (1968). 4091:Elkin, Michael (2011). 3908:Annals of Combinatorics 4305:10.4153/CMB-1968-062-3 4200:10.1006/jcta.1997.2829 3780:Computational Geometry 3771:Mitchell, Joseph S. B. 3689:Computational Geometry 3233: 3194: 3137: 3090: 3046: 3005: 2983: 2960: 2902: 2864: 2826:upper bound is known. 2820: 2797: 2753: 2719: 2671: 2643: 2590: 2546:points per line, with 2540: 2520: 2491: 2467: 2445: 2423: 2390: 2352: 2318:computational geometry 2294: 2246: 2205: 2184: 2156: 2126: 2101: 2077: 2018: 1977: 1954: 1894: 1869:Guy & Kelly (1968) 1861: 1830: 1798: 1776: 1744: 1696: 1668: 1646: 1616: 1594: 1565: 1533: 1490: 1455: 1429: 1428:{\displaystyle n-o(n)} 1392: 1370: 1344: 1322: 1302: 1282:grid contained in the 1276: 1250: 1228: 1193: 1170: 1133: 1109: 1084: 1076: 1056: 1039: 1000: 966: 917: 894: 855: 828: 808: 782: 749: 725: 705:Upper and lower bounds 682: 641: 613: 593: 566: 546: 520: 495: 464: 270: 245: 214: 189: 167: 147: 120: 91: 57: 26: 4917:Mathematical problems 4576:-dimensional torus". 3511:Payne & Wood 2013 3234: 3195: 3138: 3091: 3047: 3006: 2984: 2961: 2903: 2865: 2836:Pór & Wood (2007) 2821: 2798: 2754: 2720: 2672: 2644: 2591: 2541: 2521: 2492: 2468: 2446: 2424: 2396:can be obtained by a 2391: 2353: 2295: 2247: 2206: 2185: 2157: 2127: 2102: 2078: 2019: 1978: 1955: 1895: 1862: 1831: 1799: 1777: 1745: 1697: 1669: 1654:Again, for arbitrary 1647: 1617: 1595: 1566: 1534: 1491: 1456: 1430: 1393: 1376:will always be close 1371: 1345: 1323: 1303: 1277: 1251: 1229: 1194: 1171: 1134: 1110: 1077: 1057: 1040: 1001: 999:{\displaystyle (4,5)} 967: 918: 895: 856: 829: 809: 783: 767: 750: 726: 683: 642: 614: 594: 567: 547: 521: 496: 465: 271: 246: 215: 190: 168: 148: 121: 92: 58: 24: 4864:Flammenkamp, Achim. 4615:Discrete Mathematics 4360:Discrete Mathematics 3695:. Elsevier: 101913. 3408:Guy & Kelly 1968 3205: 3178: 3115: 3056: 3030: 2995: 2970: 2915: 2876: 2842: 2807: 2763: 2737: 2703: 2661: 2604: 2551: 2530: 2510: 2481: 2457: 2435: 2413: 2367: 2342: 2260: 2221: 2195: 2174: 2140: 2113: 2091: 2067: 1987: 1964: 1906: 1881: 1848: 1814: 1808:pigeonhole principle 1788: 1763: 1707: 1678: 1658: 1628: 1606: 1576: 1564:{\displaystyle xy=k} 1546: 1500: 1472: 1439: 1404: 1382: 1360: 1334: 1312: 1286: 1260: 1240: 1206: 1180: 1144: 1123: 1099: 1066: 1050: 1010: 1006:is included because 978: 929: 904: 868: 854:{\displaystyle p=11} 839: 818: 792: 772: 739: 715: 669: 625: 603: 580: 556: 530: 507: 485: 448: 257: 244:{\displaystyle 3n/2} 224: 201: 179: 157: 134: 128:pigeonhole principle 119:{\displaystyle 2n+1} 101: 78: 41: 4829:-colourable graphs" 4684:Payne, Michael S.; 4265:Scientific American 4012:, November 7, 1906. 3894:Cooper, Joshua N.; 3679:Aichholzer, Oswin; 3547:Pór & Wood 2007 3348:; Flammenkamp  3283:The Weekly Dispatch 3252:Eight queens puzzle 2752:{\displaystyle n-1} 2681:entropy compression 2362:approximation ratio 2155:{\displaystyle k=n} 1695:{\displaystyle n/2} 1645:{\displaystyle n/2} 1593:{\displaystyle n/2} 1489:{\displaystyle n/2} 640:{\displaystyle n=2} 463:{\displaystyle n=8} 4875:Weisstein, Eric W. 4825:"Grid drawings of 4740:"Chessboard Tasks" 4738:(April 11, 2005). 4410:10.1007/BF01216795 3664:10.1007/BFb0057371 3638:Ku & Wong 2018 3614:Misiak et al. 2016 3523:Cooper et al. 2014 3496:Froese et al. 2017 3229: 3190: 3133: 3086: 3042: 3024:Salem–Spencer sets 3001: 2982:{\displaystyle p)} 2979: 2956: 2898: 2860: 2819:{\displaystyle 2n} 2816: 2793: 2749: 2715: 2667: 2639: 2586: 2539:{\textstyle \ell } 2536: 2516: 2487: 2463: 2441: 2419: 2386: 2348: 2290: 2242: 2201: 2180: 2152: 2125:{\displaystyle nk} 2122: 2097: 2073: 2014: 1976:{\displaystyle cn} 1973: 1950: 1893:{\displaystyle cn} 1890: 1860:{\displaystyle 2n} 1857: 1840:Conjectured bounds 1826: 1794: 1775:{\displaystyle 2n} 1772: 1740: 1720: 1692: 1664: 1642: 1612: 1590: 1561: 1529: 1486: 1466:Hall et al. (1975) 1451: 1425: 1388: 1366: 1340: 1318: 1298: 1272: 1246: 1224: 1192:{\displaystyle n)} 1189: 1166: 1129: 1105: 1085: 1075:{\displaystyle 11} 1072: 1035: 996: 962: 916:{\displaystyle p)} 913: 890: 851: 824: 804: 781:{\displaystyle 11} 778: 745: 721: 681:{\displaystyle 2n} 678: 637: 609: 592:{\displaystyle 2n} 589: 562: 542: 519:{\displaystyle 2n} 516: 491: 460: 269:{\displaystyle 2n} 266: 241: 213:{\displaystyle 2n} 210: 188:{\displaystyle 46} 185: 163: 146:{\displaystyle 2n} 143: 116: 90:{\displaystyle 2n} 87: 53: 27: 4712:10.1137/120897493 4210:Niedermeier, Rolf 3829:978-0-387-29929-7 3433:Brass et al. 2007 3365:Flammenkamp  3004:{\displaystyle p} 2830:Higher dimensions 2670:{\displaystyle S} 2634: 2581: 2519:{\displaystyle S} 2490:{\displaystyle k} 2466:{\displaystyle n} 2444:{\displaystyle k} 2422:{\displaystyle k} 2381: 2351:{\displaystyle k} 2183:{\displaystyle n} 2100:{\displaystyle k} 2076:{\displaystyle n} 2006: 2005: 1942: 1936: 1844:Although exactly 1797:{\displaystyle n} 1719: 1667:{\displaystyle n} 1615:{\displaystyle k} 1391:{\displaystyle n} 1369:{\displaystyle p} 1343:{\displaystyle n} 1321:{\displaystyle p} 1249:{\displaystyle n} 1132:{\displaystyle n} 1108:{\displaystyle n} 827:{\displaystyle p} 748:{\displaystyle n} 724:{\displaystyle n} 612:{\displaystyle n} 565:{\displaystyle n} 494:{\displaystyle n} 474:squares d4 and e5 427: 426: 166:{\displaystyle n} 153:points for every 35:discrete geometry 4924: 4888: 4887: 4869: 4852: 4850: 4828: 4816: 4790: 4755: 4753: 4751: 4731: 4705: 4696:(4): 1727–1733. 4680: 4678: 4656: 4630: 4609: 4575: 4568: 4557:Knuth, Donald E. 4552: 4510: 4479: 4469: 4442: 4429: 4386: 4376: 4346: 4344: 4317: 4307: 4277: 4255: 4229: 4204: 4202: 4175: 4173: 4146: 4134: 4124: 4114: 4087: 4069: 4035: 4003: 3987: 3977: 3950: 3924: 3904: 3896:Solymosi, József 3890: 3864: 3841: 3806: 3796: 3761: 3751: 3724: 3714: 3704: 3675: 3641: 3635: 3629: 3623: 3617: 3611: 3605: 3599: 3593: 3587: 3581: 3575: 3569: 3556: 3550: 3544: 3538: 3532: 3526: 3520: 3514: 3508: 3502: 3493: 3487: 3481: 3472: 3466: 3460: 3454: 3448: 3442: 3436: 3430: 3424: 3417: 3411: 3405: 3399: 3396:Hall et al. 1975 3393: 3387: 3380: 3374: 3363: 3357: 3327: 3321: 3315: 3309: 3303: 3290: 3280: 3274: 3268: 3240: 3238: 3236: 3235: 3230: 3199: 3197: 3196: 3191: 3156: 3152: 3142: 3140: 3139: 3134: 3095: 3093: 3092: 3087: 3082: 3081: 3077: 3051: 3049: 3048: 3043: 3014: 3010: 3008: 3007: 3002: 2990: 2988: 2986: 2985: 2980: 2965: 2963: 2962: 2957: 2955: 2954: 2942: 2941: 2909: 2907: 2905: 2904: 2899: 2894: 2893: 2869: 2867: 2866: 2861: 2825: 2823: 2822: 2817: 2802: 2800: 2799: 2794: 2789: 2788: 2784: 2758: 2756: 2755: 2750: 2731:greedy algorithm 2724: 2722: 2721: 2716: 2687:Greedy placement 2678: 2676: 2674: 2673: 2668: 2650: 2648: 2646: 2645: 2640: 2635: 2633: 2625: 2620: 2597: 2595: 2593: 2592: 2587: 2582: 2580: 2572: 2567: 2545: 2543: 2542: 2537: 2525: 2523: 2522: 2517: 2498: 2496: 2494: 2493: 2488: 2474: 2472: 2470: 2469: 2464: 2450: 2448: 2447: 2442: 2430: 2428: 2426: 2425: 2420: 2398:greedy algorithm 2395: 2393: 2392: 2387: 2382: 2377: 2359: 2357: 2355: 2354: 2349: 2322:general position 2301: 2299: 2297: 2296: 2291: 2286: 2285: 2276: 2253: 2251: 2249: 2248: 2243: 2238: 2233: 2232: 2210: 2208: 2207: 2202: 2189: 2187: 2186: 2181: 2163: 2161: 2159: 2158: 2153: 2133: 2131: 2129: 2128: 2123: 2106: 2104: 2103: 2098: 2082: 2080: 2079: 2074: 2023: 2021: 2020: 2015: 2007: 2001: 1997: 1982: 1980: 1979: 1974: 1959: 1957: 1956: 1951: 1943: 1941: 1932: 1931: 1930: 1917: 1916: 1901: 1899: 1897: 1896: 1891: 1866: 1864: 1863: 1858: 1835: 1833: 1832: 1827: 1805: 1803: 1801: 1800: 1795: 1781: 1779: 1778: 1773: 1751: 1749: 1747: 1746: 1741: 1721: 1712: 1701: 1699: 1698: 1693: 1688: 1673: 1671: 1670: 1665: 1653: 1651: 1649: 1648: 1643: 1638: 1621: 1619: 1618: 1613: 1601: 1599: 1597: 1596: 1591: 1586: 1570: 1568: 1567: 1562: 1538: 1536: 1535: 1530: 1525: 1495: 1493: 1492: 1487: 1482: 1468:show that, when 1460: 1458: 1457: 1452: 1434: 1432: 1431: 1426: 1399: 1397: 1395: 1394: 1389: 1375: 1373: 1372: 1367: 1351: 1349: 1347: 1346: 1341: 1327: 1325: 1324: 1319: 1307: 1305: 1304: 1299: 1281: 1279: 1278: 1273: 1255: 1253: 1252: 1247: 1235: 1233: 1231: 1230: 1225: 1200: 1198: 1196: 1195: 1190: 1175: 1173: 1172: 1167: 1165: 1164: 1138: 1136: 1135: 1130: 1114: 1112: 1111: 1106: 1083: 1081: 1079: 1078: 1073: 1061: 1059: 1058: 1055:{\displaystyle } 1053: 1044: 1042: 1041: 1036: 1022: 1021: 1005: 1003: 1002: 997: 973: 971: 969: 968: 963: 923: 922: 920: 919: 914: 899: 897: 896: 891: 889: 888: 862: 860: 858: 857: 852: 833: 831: 830: 825: 813: 811: 810: 805: 787: 785: 784: 779: 756: 754: 752: 751: 746: 732: 730: 728: 727: 722: 696: 687: 685: 684: 679: 657: 648: 646: 644: 643: 638: 618: 616: 615: 610: 598: 596: 595: 590: 575: 571: 569: 568: 563: 551: 549: 548: 543: 525: 523: 522: 517: 502: 500: 498: 497: 492: 471: 469: 467: 466: 461: 421: 420: 414: 413: 407: 406: 400: 399: 393: 392: 386: 385: 379: 378: 372: 371: 365: 364: 358: 357: 351: 350: 344: 343: 337: 336: 330: 329: 323: 322: 316: 315: 310: 309: 302: 277: 275: 273: 272: 267: 250: 248: 247: 242: 237: 219: 217: 216: 211: 196: 194: 192: 191: 186: 172: 170: 169: 164: 152: 150: 149: 144: 125: 123: 122: 117: 96: 94: 93: 88: 62: 60: 59: 54: 4932: 4931: 4927: 4926: 4925: 4923: 4922: 4921: 4892: 4891: 4873: 4872: 4863: 4860: 4855: 4826: 4819: 4793: 4758: 4749: 4747: 4734: 4683: 4659: 4612: 4573: 4571: 4555: 4513: 4482: 4445: 4432: 4389: 4351:Harborth, Heiko 4349: 4320: 4280: 4260:Gardner, Martin 4258: 4207: 4178: 4149: 4139:Eppstein, David 4137: 4090: 4038: 4015: 3990: 3953: 3902: 3893: 3844: 3830: 3809: 3764: 3727: 3681:Eppstein, David 3678: 3653: 3649: 3644: 3636: 3632: 3624: 3620: 3612: 3608: 3600: 3596: 3588: 3584: 3576: 3572: 3557: 3553: 3545: 3541: 3533: 3529: 3521: 3517: 3509: 3505: 3494: 3490: 3482: 3475: 3467: 3463: 3455: 3451: 3443: 3439: 3431: 3427: 3419:As reported by 3418: 3414: 3406: 3402: 3394: 3390: 3381: 3377: 3364: 3360: 3328: 3324: 3316: 3312: 3304: 3293: 3281: 3277: 3269: 3265: 3261: 3248: 3203: 3202: 3201: 3176: 3175: 3163: 3154: 3144: 3113: 3112: 3065: 3054: 3053: 3052:grid have only 3028: 3027: 3012: 2993: 2992: 2968: 2967: 2946: 2933: 2913: 2912: 2911: 2885: 2874: 2873: 2871: 2840: 2839: 2832: 2805: 2804: 2772: 2761: 2760: 2735: 2734: 2701: 2700: 2689: 2659: 2658: 2656: 2653:polynomial-time 2602: 2601: 2599: 2549: 2548: 2547: 2528: 2527: 2526:having at most 2508: 2507: 2506:For point sets 2479: 2478: 2476: 2455: 2454: 2452: 2433: 2432: 2411: 2410: 2408: 2365: 2364: 2340: 2339: 2337: 2314: 2309: 2277: 2258: 2257: 2256: 2224: 2219: 2218: 2216: 2193: 2192: 2172: 2171: 2138: 2137: 2135: 2111: 2110: 2108: 2089: 2088: 2083:vertices and a 2065: 2064: 2029: 1985: 1984: 1962: 1961: 1922: 1918: 1904: 1903: 1879: 1878: 1876: 1846: 1845: 1842: 1812: 1811: 1786: 1785: 1783: 1761: 1760: 1757: 1705: 1704: 1703: 1676: 1675: 1656: 1655: 1626: 1625: 1623: 1604: 1603: 1574: 1573: 1571: 1544: 1543: 1498: 1497: 1470: 1469: 1437: 1436: 1402: 1401: 1380: 1379: 1377: 1358: 1357: 1332: 1331: 1329: 1310: 1309: 1284: 1283: 1258: 1257: 1238: 1237: 1204: 1203: 1202: 1178: 1177: 1156: 1142: 1141: 1140: 1121: 1120: 1097: 1096: 1091:, published by 1064: 1063: 1048: 1047: 1045: 1013: 1008: 1007: 976: 975: 927: 926: 925: 902: 901: 880: 866: 865: 864: 837: 836: 835: 816: 815: 790: 789: 770: 769: 762: 737: 736: 734: 713: 712: 710: 707: 702: 692: 667: 666: 663: 653: 623: 622: 620: 601: 600: 578: 577: 573: 554: 553: 528: 527: 505: 504: 483: 482: 480: 446: 445: 443: 432: 431: 430: 423: 422: 415: 408: 401: 394: 387: 380: 373: 366: 359: 352: 345: 338: 331: 324: 317: 307: 298: 296:Small instances 255: 254: 252: 222: 221: 199: 198: 177: 176: 174: 155: 154: 132: 131: 99: 98: 76: 75: 39: 38: 19: 12: 11: 5: 4930: 4928: 4920: 4919: 4914: 4909: 4907:Lattice points 4904: 4894: 4893: 4890: 4889: 4870: 4859: 4858:External links 4856: 4854: 4853: 4821:Wood, David R. 4817: 4807:(3): 198–204. 4791: 4761:Wood, David R. 4756: 4732: 4686:Wood, David R. 4681: 4657: 4621:(1): 217–221. 4610: 4584:(2): 355–364. 4569: 4567:. p. 130. 4553: 4511: 4480: 4460:(1): 126–127. 4443: 4430: 4404:(1): 500–518. 4387: 4367:(1–2): 89–90. 4347: 4335:(3): 336–341. 4318: 4298:(4): 527–531. 4278: 4256: 4220:(4): 277–296. 4205: 4193:(1): 108–113. 4176: 4164:(2): 305–311. 4147: 4135: 4088: 4060:(3): 553–579. 4048:Wood, David R. 4040:Dujmović, Vida 4036: 4013: 3992:Dudeney, Henry 3988: 3968:(3): 363–364. 3951: 3915:(2): 169–175. 3891: 3855:(3): 213–221. 3842: 3828: 3807: 3787:(2): 117–130. 3762: 3742:(3): 365–366. 3725: 3676: 3650: 3648: 3645: 3643: 3642: 3630: 3618: 3606: 3602:Klarreich 2016 3594: 3582: 3570: 3551: 3539: 3527: 3515: 3503: 3488: 3473: 3461: 3449: 3437: 3425: 3412: 3400: 3388: 3375: 3358: 3322: 3310: 3291: 3275: 3262: 3260: 3257: 3256: 3255: 3247: 3244: 3228: 3225: 3222: 3219: 3216: 3213: 3210: 3189: 3186: 3183: 3162: 3159: 3132: 3129: 3126: 3123: 3120: 3096:vertices. The 3085: 3080: 3076: 3072: 3068: 3064: 3061: 3041: 3038: 3035: 3000: 2978: 2975: 2953: 2949: 2945: 2940: 2936: 2932: 2929: 2926: 2923: 2920: 2897: 2892: 2888: 2884: 2881: 2859: 2856: 2853: 2850: 2847: 2831: 2828: 2815: 2812: 2792: 2787: 2783: 2779: 2775: 2771: 2768: 2748: 2745: 2742: 2714: 2711: 2708: 2697:Martin Gardner 2688: 2685: 2666: 2638: 2632: 2628: 2624: 2618: 2615: 2612: 2609: 2585: 2579: 2575: 2571: 2565: 2562: 2559: 2556: 2535: 2515: 2486: 2462: 2440: 2418: 2385: 2380: 2375: 2372: 2347: 2313: 2310: 2308: 2305: 2289: 2284: 2280: 2275: 2271: 2268: 2265: 2241: 2237: 2231: 2227: 2213:Pick's theorem 2200: 2179: 2151: 2148: 2145: 2121: 2118: 2096: 2085:graph coloring 2072: 2061:graph coloring 2057:complete graph 2028: 2025: 2013: 2010: 2004: 2000: 1995: 1992: 1972: 1969: 1949: 1946: 1940: 1935: 1929: 1925: 1921: 1914: 1911: 1889: 1886: 1856: 1853: 1841: 1838: 1825: 1822: 1819: 1793: 1771: 1768: 1756: 1753: 1739: 1736: 1733: 1730: 1727: 1724: 1718: 1715: 1691: 1687: 1683: 1663: 1641: 1637: 1633: 1611: 1589: 1585: 1581: 1560: 1557: 1554: 1551: 1528: 1524: 1520: 1517: 1514: 1511: 1508: 1505: 1485: 1481: 1477: 1450: 1447: 1444: 1435:points in the 1424: 1421: 1418: 1415: 1412: 1409: 1387: 1365: 1339: 1317: 1297: 1294: 1291: 1271: 1268: 1265: 1245: 1223: 1220: 1217: 1214: 1211: 1188: 1185: 1163: 1159: 1155: 1152: 1149: 1128: 1104: 1087:A solution of 1071: 1034: 1031: 1028: 1025: 1020: 1016: 995: 992: 989: 986: 983: 974:For instance, 961: 958: 955: 952: 949: 946: 943: 940: 937: 934: 912: 909: 887: 883: 879: 876: 873: 850: 847: 844: 823: 803: 800: 797: 777: 761: 758: 744: 720: 706: 703: 690: 677: 674: 651: 636: 633: 630: 608: 588: 585: 561: 541: 538: 535: 515: 512: 490: 459: 456: 453: 428: 425: 424: 416: 409: 402: 395: 388: 381: 374: 367: 360: 353: 346: 339: 332: 325: 318: 311: 305: 300: 299: 297: 294: 265: 262: 240: 236: 232: 229: 209: 206: 184: 162: 142: 139: 115: 112: 109: 106: 86: 83: 52: 49: 46: 17: 13: 10: 9: 6: 4: 3: 2: 4929: 4918: 4915: 4913: 4910: 4908: 4905: 4903: 4902:Combinatorics 4900: 4899: 4897: 4885: 4884: 4879: 4876: 4871: 4867: 4862: 4861: 4857: 4849: 4844: 4840: 4836: 4835: 4830: 4822: 4818: 4814: 4810: 4806: 4802: 4801: 4796: 4792: 4788: 4784: 4780: 4776: 4772: 4768: 4767: 4762: 4759:Pór, Attila; 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Retrieved 4743: 4736:Pegg, Ed Jr. 4693: 4689: 4664: 4618: 4614: 4581: 4577: 4564: 4535:(1): 13–24. 4532: 4526: 4493:(1): 82–83. 4490: 4489:. Series A. 4484: 4457: 4456:. Series A. 4451: 4438: 4401: 4395: 4364: 4358: 4332: 4331:. Series A. 4326: 4295: 4289: 4263: 4217: 4213: 4190: 4189:. Series A. 4184: 4161: 4160:. Series A. 4155: 4142: 4102: 4096: 4057: 4051: 4026:(1): 26–58. 4023: 4017: 4009: 3999: 3965: 3964:. Series A. 3959: 3922:math/0408396 3912: 3906: 3852: 3846: 3819: 3784: 3778: 3739: 3738:. Series A. 3733: 3692: 3688: 3655: 3633: 3621: 3609: 3597: 3585: 3573: 3554: 3542: 3530: 3518: 3506: 3491: 3464: 3452: 3440: 3428: 3415: 3403: 3391: 3378: 3361: 3325: 3318:Dudeney 1917 3313: 3306:Gardner 1976 3282: 3278: 3266: 3164: 3110: 3017: 2833: 2690: 2505: 2402: 2315: 2165: 2033:degeneracies 2030: 2027:Applications 1843: 1758: 1463: 1352:Because the 1308:grid, where 1139:grid points 1117:prime number 1086: 708: 664: 478: 433: 279: 73: 30: 28: 15: 4912:Conjectures 4795:Roth, K. F. 4661:Pach, János 4006:p. 222 3812:Pach, János 3767:Lubiw, Anna 3590:Jarník 1926 3155:N = 2, 3, 4 3020:hypersphere 2330:approximate 1873:upper bound 1755:Upper bound 1093:Roth (1951) 619:, starting 288:and to the 4896:Categories 4773:(4): 481. 4744:Math Games 4515:Komlós, J. 4282:Guy, R. K. 4227:1508.01097 4105:: 93–128. 4067:cs/0406024 4044:Morin, Pat 4004:Solution, 3702:2203.13170 3647:References 3578:Elkin 2011 3287:Knuth 2008 1089:Paul Erdős 788:points in 440:chessboard 4883:MathWorld 4787:209841346 4703:1208.5289 4628:1406.6713 4519:Pintz, J. 4426:117747514 4112:0801.4310 3862:1206.5350 3721:249687906 3457:Roth 1951 3445:Wood 2005 3421:Pegg 2005 3384:Roth 1951 3185:× 3169:by using 3128:× 3122:× 3037:× 2880:Θ 2855:× 2849:× 2767:Ω 2744:− 2710:× 2608:ℓ 2555:ℓ 2534:ℓ 2264:Ω 2226:ε 2199:ε 2009:≈ 1999:π 1945:≈ 1924:π 1821:≤ 1726:− 1541:hyperbola 1513:− 1446:× 1411:− 1293:× 1267:× 1213:≤ 1030:≅ 957:− 951:… 799:× 537:× 48:× 4823:(2005). 4750:June 25, 4653:40210322 4559:(2008). 4274:24950467 4252:47260245 3994:(1917). 3947:11035679 3898:(2005). 3814:(2005). 3773:(2007). 3246:See also 2727:superset 2334:APX-hard 2041:vertices 1759:At most 251:points, 74:At most 4728:7164626 4720:3111653 4645:3404483 4606:3935268 4598:3774457 4549:0645860 4507:0525088 4476:0462998 4418:1544776 4383:0974815 4314:0238765 4244:3766097 4131:2823971 4084:3264071 4010:Tribune 3984:0406804 3939:2153735 3838:2163782 3803:2278011 3758:0555806 3672:0349396 3157:, etc. 3150:A280537 3148::  3098:cap set 3013:3 mod 4 2326:NP-hard 1750:points. 697:in the 694:A000769 658:in the 655:A000755 4785:  4726:  4718:  4651:  4643:  4604:  4596:  4547:  4505:  4474:  4439:Quanta 4424:  4416:  4381:  4312:  4272:  4250:  4242:  4129:  4082:  3982:  3945:  3937:  3887:887220 3885:  3877:  3836:  3826:  3801:  3756:  3719:  3670:  2991:where 2217:least 2012:1.814. 1948:1.874. 1602:where 574:to 46, 65:slopes 4783:S2CID 4724:S2CID 4698:arXiv 4649:S2CID 4623:arXiv 4602:S2CID 4422:S2CID 4270:JSTOR 4248:S2CID 4222:arXiv 4107:arXiv 4080:S2CID 4062:arXiv 3943:S2CID 3917:arXiv 3903:(PDF) 3883:S2CID 3875:JSTOR 3857:arXiv 3717:S2CID 3697:arXiv 3259:Notes 3167:torus 3161:Torus 3104:over 2453:size 2409:size 2338:size 2136:with 2087:with 2045:edges 1983:with 1902:with 1877:than 1784:size 1572:(mod 1330:most 1115:is a 621:from 444:case 4752:2012 3824:ISBN 3371:1998 3367:1992 3354:1998 3350:1992 3338:1979 3334:1978 3153:for 3146:OEIS 2966:mod 1624:mod 1219:< 1201:for 1176:mod 1062:mod 924:for 900:mod 699:OEIS 660:OEIS 649:are 253:not 29:The 4843:doi 4809:doi 4775:doi 4708:doi 4671:doi 4633:doi 4619:339 4586:doi 4537:doi 4495:doi 4462:doi 4406:doi 4369:doi 4337:doi 4300:doi 4232:doi 4195:doi 4166:doi 4117:doi 4103:184 4072:doi 4028:doi 3970:doi 3927:doi 3867:doi 3853:121 3789:doi 3744:doi 3707:doi 3693:108 3660:doi 3212:gcd 2872:is 2657:of 2600:to 2477:on 2316:In 2109:to 2035:in 1378:to 735:to 711:of 572:up 481:of 175:to 173:up 33:in 4898:: 4880:. 4839:30 4837:. 4831:. 4805:26 4803:. 4781:. 4771:47 4769:. 4742:. 4722:. 4716:MR 4714:. 4706:. 4694:27 4692:. 4647:. 4641:MR 4639:. 4631:. 4617:. 4600:. 4594:MR 4592:. 4582:34 4580:. 4563:. 4545:MR 4543:. 4533:25 4531:. 4521:; 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846:= 843:p 822:p 755:. 743:n 731:, 719:n 676:n 673:2 647:, 635:2 632:= 629:n 607:n 587:n 584:2 560:n 540:n 534:n 514:n 511:2 501:, 489:n 470:. 458:8 455:= 452:n 276:. 264:n 261:2 239:2 235:/ 231:n 228:3 208:n 205:2 195:, 161:n 141:n 138:2 114:1 111:+ 108:n 105:2 85:n 82:2 51:n 45:n

Index


discrete geometry
slopes
Henry Dudeney
pigeonhole principle
recreational mathematics
graph drawing
Heilbronn triangle problem
Henry Dudeney
chessboard
squares d4 and e5
A000755
OEIS
A000769
OEIS

Paul Erdős
Roth (1951)
prime number
gap between consecutive primes
Hall et al. (1975)
hyperbola
pigeonhole principle
Guy & Kelly (1968)
upper bound
degeneracies
graph drawing
vertices
edges
line segments

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