Experimental results: Difference between revisions
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<math>N(2, 2) | <math>N(2, 2) \geq 1124</math> | ||
--[[User:Alec|Alec]] 13:46, 9 January 2010 (UTC) | --[[User:Alec|Alec]] 13:46, 9 January 2010 (UTC) | ||
== Geometric variations == | |||
It has been pointed out that the problem can be generalized to higher dimensions, for example by considering sequences with <math>\Vert x_n \Vert_2 = 1</math> having partial sums lying within a sphere. It is difficult to do much in the way of computation when the <math>x_n</math> can vary continuously, but if they are restricted to some finite set the problem becomes purely combinatorial and one can do more. | |||
=== The seven-point hexagon === | |||
If the <math>x_n</math> are allowed to be any of the six points of a regular hexagon, and one requires all sums along HAPs to be zero or one of those same points, the maximum length of a sequence is <math>116</math>. The following sequence achieves this, where the numbers index the points in order around the hexagon: | |||
0, 3, 3, 0, 3, 0, 2, 4, 0, 1, 4, 3, 1, 5, 0, 2, 4, 3, 1, 5, 5, 1, 4, 1, 2, 5, 3, 2, 5, 4, 1, 4, 1, 2, 5, 0, 2, 4, 4, 1, 5, 2, 1, 4, 3, 1, 5, 5, 2, 4, 1, 2, 4, 0, 1, 5, 4, 1, 4, 2, 2, 4, 0, 1, 5, 4, 2, 5, 1, 2, 4, 3, 1, 5, 5, 1, 4, 1, 3, 4, 2, 1, 0, 4, 1, 4, 3, 1, 5, 0, 2, 4, 5, 2, 4, 1, 1, 5, 3, 2, 0, 3, 4, 5, 1, 1, 3, 4, 1, 5, 0, 2, 4, 1, 3, 5 | |||
=== The nine-point square === | |||
If the <math>x_n</math> are allowed to be any of the four points <math>(\pm 1, 0)</math> and <math>(0, \pm 1)</math>, and one requires all sums along HAPs to belong to one of the nine points at unit spacing centred on the origin, the maximum length of a sequence is ''at least'' <math>314</math>. The following sequence achieves this: | |||
(1, 0), (0, 1), (-1, 0), (1, 0), (-1, 0), (0, -1), (0, 1), (-1, 0), (1, 0), (1, 0), (0, -1), (-1, 0), (-1, 0), (0, -1), (1, 0), (1, 0), (-1, 0), (0, 1), (1, 0), (-1, 0), (0, -1), (-1, 0), (0, 1), (1, 0), (0, -1), (1, 0), (-1, 0), (0, 1), (1, 0), (-1, 0), (0, -1), (-1, 0), (0, 1), (0, -1), (1, 0), (1, 0), (-1, 0), (-1, 0), (1, 0), (1, 0), (0, 1), (0, 1), (-1, 0), (0, -1), (-1, 0), (1, 0), (1, 0), (-1, 0), (0, -1), (0, 1), (1, 0), (-1, 0), (1, 0), (0, -1), (0, 1), (0, -1), (-1, 0), (0, 1), (-1, 0), (1, 0), (0, -1), (-1, 0), (0, 1), (1, 0), (0, -1), (1, 0), (0, 1), (0, 1), (0, -1), (-1, 0), (1, 0), (-1, 0), (-1, 0), (1, 0), (0, 1), (1, 0), (-1, 0), (-1, 0), (1, 0), (-1, 0), (1, 0), (0, -1), (0, 1), (0, -1), (0, -1), (0, 1), (-1, 0), (0, 1), (0, -1), (1, 0), (1, 0), (-1, 0), (0, 1), (0, -1), (0, 1), (1, 0), (0, -1), (0, 1), (0, -1), (0, -1), (0, 1), (0, 1), (-1, 0), (1, 0), (-1, 0), (0, -1), (1, 0), (-1, 0), (-1, 0), (0, -1), (1, 0), (0, 1), (-1, 0), (1, 0), (1, 0), (0, -1), (-1, 0), (0, 1), (1, 0), (-1, 0), (1, 0), (-1, 0), (0, -1), (1, 0), (0, 1), (0, -1), (-1, 0), (-1, 0), (1, 0), (0, 1), (0, -1), (0, 1), (-1, 0), (1, 0), (1, 0), (0, -1), (0, 1), (-1, 0), (0, -1), (1, 0), (-1, 0), (0, 1), (0, 1), (1, 0), (-1, 0), (0, -1), (0, 1), (-1, 0), (1, 0), (0, -1), (1, 0), (-1, 0), (-1, 0), (1, 0), (0, 1), (1, 0), (0, -1), (-1, 0), (-1, 0), (1, 0), (0, -1), (0, 1), (0, 1), (-1, 0), (0, -1), (0, -1), (0, 1), (0, 1), (0, -1), (0, 1), (1, 0), (1, 0), (-1, 0), (0, -1), (-1, 0), (0, -1), (1, 0), (0, 1), (1, 0), (-1, 0), (0, -1), (-1, 0), (0, 1), (1, 0), (0, -1), (1, 0), (0, 1), (0, 1), (0, -1), (0, -1), (0, 1), (-1, 0), (-1, 0), (1, 0), (0, 1), (0, -1), (1, 0), (-1, 0), (0, -1), (0, 1), (0, -1), (-1, 0), (0, 1), (0, -1), (1, 0), (1, 0), (0, 1), (-1, 0), (0, -1), (1, 0), (0, 1), (0, 1), (-1, 0), (-1, 0), (0, -1), (1, 0), (-1, 0), (1, 0), (1, 0), (0, 1), (0, -1), (-1, 0), (0, 1), (0, -1), (0, -1), (1, 0), (0, 1), (-1, 0), (1, 0), (-1, 0), (1, 0), (0, 1), (-1, 0), (1, 0), (-1, 0), (1, 0), (-1, 0), (-1, 0), (1, 0), (1, 0), (0, -1), (-1, 0), (-1, 0), (0, -1), (1, 0), (0, 1), (0, 1), (-1, 0), (0, -1), (0, -1), (1, 0), (0, 1), (-1, 0), (1, 0), (0, 1), (1, 0), (-1, 0), (-1, 0), (1, 0), (-1, 0), (1, 0), (1, 0), (-1, 0), (0, -1), (0, -1), (0, 1), (0, 1), (0, -1), (1, 0), (-1, 0), (-1, 0), (0, 1), (0, -1), (1, 0), (0, 1), (1, 0), (-1, 0), (-1, 0), (0, -1), (0, -1), (1, 0), (0, 1), (0, -1), (-1, 0), (1, 0), (1, 0), (0, 1), (-1, 0), (0, -1), (1, 0), (-1, 0), (1, 0), (0, 1), (0, -1), (-1, 0), (0, 1), (0, 1), (0, -1), (1, 0), (0, 1), (-1, 0), (-1, 0), (1, 0), (0, -1), (0, 1), (1, 0), (-1, 0), (-1, 0), (0, -1), (1, 0), (1, 0), (0, -1), (0, 1), (0, 1) | |||
--[[User:Alec|Alec]] 14:42, 9 January 2010 (UTC) | |||
Revision as of 06:42, 9 January 2010
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Different displays of a long low-discrepancy sequence
It would be good to have some long sequences with low discrepancy displayed nicely here (or on subsidiary pages) in tabular form, together with discussions about the structures that can be found in these sequences. For now, here is the current record not displayed in a particularly helpful way. It is a sequence of discrepancy 2 and length 1124.
The raw sequence
+ - + + - - - - + + - + + + - - + - + + - - - + - + + - + - - + + - + - - + - - + + - + + - - - + + + - - + - + - - + + + + - - + - - + + - - + + + - - + + - + - - + - - + + - + - - + - + + + - - + - + - - + + - - - + + - + + + - - - + - - + - + + + + - - - - + + - + + + - - + - - + - - + - + - + + - + + + - - - - + + + + - - - + + - + - - + - + + - - + - + + - + - + - + + - - - + + - + + - - + - - + - - + + + + - + - - + - - + + - - + - + + - - - + - + + - + + + - - + + - - + - - + - + + - - + - + + - + + - - + - - + - + + - - + + - + - + - - + - + + + - - + - + + - - - - + + - - + - + + - + + - - + - + + - - + + - + - - + - + - - + + - - + - + + + - + - - + - + - - + + + + - - - + + - + - - + - + + - - + - + + - + + - - + - - + - + + - - + + - - - + + - - + - + + - + + - - + - - + + + + - - - - + + - + + - + + - - + - - + + - - - + + - + + - - + - + + - + - - - + - + + - + + - - + - - + - + + - - + + - + + + - - - + - + + - + + - - + - - - + + + - - + - + - - + + + - + - + + - + - - - + + - + - + + - - + - - + - + + - - + - + - + + - + - + - - + - + + - - + - - + - + + + - - - + + - + + + - + - - + - + + - - + - + + - + - - - + - + + - + + - - + - - - + + + - - + - + + - - + + - + - + + - + - - - + - - + - + + - - + - + + - + + - - + - + + - + + - - + - - + - + + - - + - - + - + + - + - - + + - + + - - + - - + - + + - - + - + + - + + - - + - + + - - + + - + - - + - + + - - + - - + - + + - - + - + + - + + - + + - - + - + + - - + - - + - + + - - + - + - - + + + - + - - + - + + - - + - + - - + + + - - - + + - + + - - + + - + - + + - - + - - + - - + - + + - + - - + + + - + - - + - + + - - + - + - - + + - - + - + + - + + - - + + - + - - + - - + - + + - + + - - + - + + - + + - - + - - + + + - - - + - - + - + + - - + + + + - + - - + + - - + - + + - - + - - + - + + - - + - + + - + + - - + - - + - + + - - - + + - - + + - - + - + + - + + - - + - - + - + + + - + - - + - + + - - + - + + - + - + - - + - + - + + - - + - + - - + + + - + - - - + + + - - + - - + - + + - - + + + + - + - - - + - + + - + + - - + - - + + + - - - + - - + - + + + - + - + + - + - - - + - - + + + + - - + - + + - - + - + + - + - - + - + + - - - + - - + + - + - + + - + - - - + - + + + + - + - - - - + - + + - + + - - + + - + + - + - - + - + + - + - -
The sequence, together with the corresponding integers
1+ 2- 3+ 4+ 5- 6- 7- 8- 9+ 10+ 11- 12+ 13+ 14+ 15- 16- 17+ 18- 19+ 20+ 21- 22- 23- 24+ 25- 26+ 27+ 28- 29+ 30- 31- 32+ 33+ 34- 35+ 36- 37- 38+ 39- 40- 41+ 42+ 43- 44+ 45+ 46- 47- 48- 49+ 50+ 51+ 52- 53- 54+ 55- 56+ 57- 58- 59+ 60+ 61+ 62+ 63- 64- 65+ 66- 67- 68+ 69+ 70- 71- 72+ 73+ 74+ 75- 76- 77+ 78+ 79- 80+ 81- 82- 83+ 84- 85- 86+ 87+ 88- 89+ 90- 91- 92+ 93- 94+ 95+ 96+ 97- 98- 99+ 100- 101+ 102- 103- 104+ 105+ 106- 107- 108- 109+ 110+ 111- 112+ 113+ 114+ 115- 116- 117- 118+ 119- 120- 121+ 122- 123+ 124+ 125+ 126+ 127- 128- 129- 130- 131+ 132+ 133- 134+ 135+ 136+ 137- 138- 139+ 140- 141- 142+ 143- 144- 145+ 146- 147+ 148- 149+ 150+ 151- 152+ 153+ 154+ 155- 156- 157- 158- 159+ 160+ 161+ 162+ 163- 164- 165- 166+ 167+ 168- 169+ 170- 171- 172+ 173- 174+ 175+ 176- 177- 178+ 179- 180+ 181+ 182- 183+ 184- 185+ 186- 187+ 188+ 189- 190- 191- 192+ 193+ 194- 195+ 196+ 197- 198- 199+ 200- 201- 202+ 203- 204- 205+ 206+ 207+ 208+ 209- 210+ 211- 212- 213+ 214- 215- 216+ 217+ 218- 219- 220+ 221- 222+ 223+ 224- 225- 226- 227+ 228- 229+ 230+ 231- 232+ 233+ 234+ 235- 236- 237+ 238+ 239- 240- 241+ 242- 243- 244+ 245- 246+ 247+ 248- 249- 250+ 251- 252+ 253+ 254- 255+ 256+ 257- 258- 259+ 260- 261- 262+ 263- 264+ 265+ 266- 267- 268+ 269+ 270- 271+ 272- 273+ 274- 275- 276+ 277- 278+ 279+ 280+ 281- 282- 283+ 284- 285+ 286+ 287- 288- 289- 290- 291+ 292+ 293- 294- 295+ 296- 297+ 298+ 299- 300+ 301+ 302- 303- 304+ 305- 306+ 307+ 308- 309- 310+ 311+ 312- 313+ 314- 315- 316+ 317- 318+ 319- 320- 321+ 322+ 323- 324- 325+ 326- 327+ 328+ 329+ 330- 331+ 332- 333- 334+ 335- 336+ 337- 338- 339+ 340+ 341+ 342+ 343- 344- 345- 346+ 347+ 348- 349+ 350- 351- 352+ 353- 354+ 355+ 356- 357- 358+ 359- 360+ 361+ 362- 363+ 364+ 365- 366- 367+ 368- 369- 370+ 371- 372+ 373+ 374- 375- 376+ 377+ 378- 379- 380- 381+ 382+ 383- 384- 385+ 386- 387+ 388+ 389- 390+ 391+ 392- 393- 394+ 395- 396- 397+ 398+ 399+ 400+ 401- 402- 403- 404- 405+ 406+ 407- 408+ 409+ 410- 411+ 412+ 413- 414- 415+ 416- 417- 418+ 419+ 420- 421- 422- 423+ 424+ 425- 426+ 427+ 428- 429- 430+ 431- 432+ 433+ 434- 435+ 436- 437- 438- 439+ 440- 441+ 442+ 443- 444+ 445+ 446- 447- 448+ 449- 450- 451+ 452- 453+ 454+ 455- 456- 457+ 458+ 459- 460+ 461+ 462+ 463- 464- 465- 466+ 467- 468+ 469+ 470- 471+ 472+ 473- 474- 475+ 476- 477- 478- 479+ 480+ 481+ 482- 483- 484+ 485- 486+ 487- 488- 489+ 490+ 491+ 492- 493+ 494- 495+ 496+ 497- 498+ 499- 500- 501- 502+ 503+ 504- 505+ 506- 507+ 508+ 509- 510- 511+ 512- 513- 514+ 515- 516+ 517+ 518- 519- 520+ 521- 522+ 523- 524+ 525+ 526- 527+ 528- 529+ 530- 531- 532+ 533- 534+ 535+ 536- 537- 538+ 539- 540- 541+ 542- 543+ 544+ 545+ 546- 547- 548- 549+ 550+ 551- 552+ 553+ 554+ 555- 556+ 557- 558- 559+ 560- 561+ 562+ 563- 564- 565+ 566- 567+ 568+ 569- 570+ 571- 572- 573- 574+ 575- 576+ 577+ 578- 579+ 580+ 581- 582- 583+ 584- 585- 586- 587+ 588+ 589+ 590- 591- 592+ 593- 594+ 595+ 596- 597- 598+ 599+ 600- 601+ 602- 603+ 604+ 605- 606+ 607- 608- 609- 610+ 611- 612- 613+ 614- 615+ 616+ 617- 618- 619+ 620- 621+ 622+ 623- 624+ 625+ 626- 627- 628+ 629- 630+ 631+ 632- 633+ 634+ 635- 636- 637+ 638- 639- 640+ 641- 642+ 643+ 644- 645- 646+ 647- 648- 649+ 650- 651+ 652+ 653- 654+ 655- 656- 657+ 658+ 659- 660+ 661+ 662- 663- 664+ 665- 666- 667+ 668- 669+ 670+ 671- 672- 673+ 674- 675+ 676+ 677- 678+ 679+ 680- 681- 682+ 683- 684+ 685+ 686- 687- 688+ 689+ 690- 691+ 692- 693- 694+ 695- 696+ 697+ 698- 699- 700+ 701- 702- 703+ 704- 705+ 706+ 707- 708- 709+ 710- 711+ 712+ 713- 714+ 715+ 716- 717+ 718+ 719- 720- 721+ 722- 723+ 724+ 725- 726- 727+ 728- 729- 730+ 731- 732+ 733+ 734- 735- 736+ 737- 738+ 739- 740- 741+ 742+ 743+ 744- 745+ 746- 747- 748+ 749- 750+ 751+ 752- 753- 754+ 755- 756+ 757- 758- 759+ 760+ 761+ 762- 763- 764- 765+ 766+ 767- 768+ 769+ 770- 771- 772+ 773+ 774- 775+ 776- 777+ 778+ 779- 780- 781+ 782- 783- 784+ 785- 786- 787+ 788- 789+ 790+ 791- 792+ 793- 794- 795+ 796+ 797+ 798- 799+ 800- 801- 802+ 803- 804+ 805+ 806- 807- 808+ 809- 810+ 811- 812- 813+ 814+ 815- 816- 817+ 818- 819+ 820+ 821- 822+ 823+ 824- 825- 826+ 827+ 828- 829+ 830- 831- 832+ 833- 834- 835+ 836- 837+ 838+ 839- 840+ 841+ 842- 843- 844+ 845- 846+ 847+ 848- 849+ 850+ 851- 852- 853+ 854- 855- 856+ 857+ 858+ 859- 860- 861- 862+ 863- 864- 865+ 866- 867+ 868+ 869- 870- 871+ 872+ 873+ 874+ 875- 876+ 877- 878- 879+ 880+ 881- 882- 883+ 884- 885+ 886+ 887- 888- 889+ 890- 891- 892+ 893- 894+ 895+ 896- 897- 898+ 899- 900+ 901+ 902- 903+ 904+ 905- 906- 907+ 908- 909- 910+ 911- 912+ 913+ 914- 915- 916- 917+ 918+ 919- 920- 921+ 922+ 923- 924- 925+ 926- 927+ 928+ 929- 930+ 931+ 932- 933- 934+ 935- 936- 937+ 938- 939+ 940+ 941+ 942- 943+ 944- 945- 946+ 947- 948+ 949+ 950- 951- 952+ 953- 954+ 955+ 956- 957+ 958- 959+ 960- 961- 962+ 963- 964+ 965- 966+ 967+ 968- 969- 970+ 971- 972+ 973- 974- 975+ 976+ 977+ 978- 979+ 980- 981- 982- 983+ 984+ 985+ 986- 987- 988+ 989- 990- 991+ 992- 993+ 994+ 995- 996- 997+ 998+ 999+ 1000+ 1001- 1002+ 1003- 1004- 1005- 1006+ 1007- 1008+ 1009+ 1010- 1011+ 1012+ 1013- 1014- 1015+ 1016- 1017- 1018+ 1019+ 1020+ 1021- 1022- 1023- 1024+ 1025- 1026- 1027+ 1028- 1029+ 1030+ 1031+ 1032- 1033+ 1034- 1035+ 1036+ 1037- 1038+ 1039- 1040- 1041- 1042+ 1043- 1044- 1045+ 1046+ 1047+ 1048+ 1049- 1050- 1051+ 1052- 1053+ 1054+ 1055- 1056- 1057+ 1058- 1059+ 1060+ 1061- 1062+ 1063- 1064- 1065+ 1066- 1067+ 1068+ 1069- 1070- 1071- 1072+ 1073- 1074- 1075+ 1076+ 1077- 1078+ 1079- 1080+ 1081+ 1082- 1083+ 1084- 1085- 1086- 1087+ 1088- 1089+ 1090+ 1091+ 1092+ 1093- 1094+ 1095- 1096- 1097- 1098- 1099+ 1100- 1101+ 1102+ 1103- 1104+ 1105+ 1106- 1107- 1108+ 1109+ 1110- 1111+ 1112+ 1113- 1114+ 1115- 1116- 1117+ 1118- 1119+ 1120+ 1121- 1122+ 1123- 1124-
Links to other displays and visually displayed information about the sequence
Here is an alternate formatting. Link.
Here is the sequence divided into groups of 6. Link.
Here is a Rauzy tree that conveys information about subsequences of the sequence: Link.
Multiplicativity properties of the 1124 sequence
The 1124 sequence is not weakly multiplicative, but it does appear to be close to a weakly multiplicative sequence. That is, if you are prepared to disregard a few "errors", then the number of distinct HAP-subsequences is 6. One can use this information to identify a quasi-multiplicative sequence that is in some sense close to the 1124 sequence. Some details can be found in the sequences of comments that begin here and here.
Varying the upper and lower bounds
If [math]\displaystyle{ N(a,b) }[/math] is the maximum length of a [math]\displaystyle{ \pm 1 }[/math] sequence with the partial sums along its HAPs bounded below by [math]\displaystyle{ -a }[/math] and above by [math]\displaystyle{ b }[/math], then:
[math]\displaystyle{ N(a, b) = N(b, a) }[/math]
[math]\displaystyle{ N(0, b) = b }[/math] (everything must be [math]\displaystyle{ +1 }[/math])
[math]\displaystyle{ N(1, 1) = 11 }[/math] (there are [math]\displaystyle{ 4 }[/math] such sequences: choose [math]\displaystyle{ x_1 }[/math], and use the constraints [math]\displaystyle{ x_n +x_{2n} = 0 }[/math] and [math]\displaystyle{ x_1 + \ldots + x_{2n} = 0 }[/math] to determine the entries up to [math]\displaystyle{ 10 }[/math]; then choose [math]\displaystyle{ x_{11} }[/math])
[math]\displaystyle{ N(1, 2) = 41 }[/math] (there are [math]\displaystyle{ 4 }[/math] such sequences -- example below)
0 + - - + - + + - + + - - +
- + + - + - - - + - + + - -
+ + - + - + + - - - + - + +
[math]\displaystyle{ N(1, 3) = 83 }[/math] (there are [math]\displaystyle{ 216 }[/math] such sequences -- example below)
0 - + - + - + + - + + - - +
- + + - - + - - + - + + - +
+ + - - - + + - + + - - + -
+ - - + + - - + - + + + - +
- - - + + - + - + - - + - +
+ - + + - - + - + - - - + +
[math]\displaystyle{ N(1, 4) = 131 }[/math] (there are [math]\displaystyle{ 87144 }[/math] such sequences -- example below)
0 + - - + - + + - - + -
+ + - + + + + - - - + -
- + - + + - - + + + - -
- + + - + - + - - + + -
+ + - - + - - + - + + +
+ - - + - + - - + + + -
+ - - - - + + - - - + +
- - + + + + - - - - + +
- + - + + + + - - + + -
+ - - - + + - - - + - -
+ + + - + + - - + - - +
[math]\displaystyle{ N(2, 2) \geq 1124 }[/math]
--Alec 13:46, 9 January 2010 (UTC)
Geometric variations
It has been pointed out that the problem can be generalized to higher dimensions, for example by considering sequences with [math]\displaystyle{ \Vert x_n \Vert_2 = 1 }[/math] having partial sums lying within a sphere. It is difficult to do much in the way of computation when the [math]\displaystyle{ x_n }[/math] can vary continuously, but if they are restricted to some finite set the problem becomes purely combinatorial and one can do more.
The seven-point hexagon
If the [math]\displaystyle{ x_n }[/math] are allowed to be any of the six points of a regular hexagon, and one requires all sums along HAPs to be zero or one of those same points, the maximum length of a sequence is [math]\displaystyle{ 116 }[/math]. The following sequence achieves this, where the numbers index the points in order around the hexagon:
0, 3, 3, 0, 3, 0, 2, 4, 0, 1, 4, 3, 1, 5, 0, 2, 4, 3, 1, 5, 5, 1, 4, 1, 2, 5, 3, 2, 5, 4, 1, 4, 1, 2, 5, 0, 2, 4, 4, 1, 5, 2, 1, 4, 3, 1, 5, 5, 2, 4, 1, 2, 4, 0, 1, 5, 4, 1, 4, 2, 2, 4, 0, 1, 5, 4, 2, 5, 1, 2, 4, 3, 1, 5, 5, 1, 4, 1, 3, 4, 2, 1, 0, 4, 1, 4, 3, 1, 5, 0, 2, 4, 5, 2, 4, 1, 1, 5, 3, 2, 0, 3, 4, 5, 1, 1, 3, 4, 1, 5, 0, 2, 4, 1, 3, 5
The nine-point square
If the [math]\displaystyle{ x_n }[/math] are allowed to be any of the four points [math]\displaystyle{ (\pm 1, 0) }[/math] and [math]\displaystyle{ (0, \pm 1) }[/math], and one requires all sums along HAPs to belong to one of the nine points at unit spacing centred on the origin, the maximum length of a sequence is at least [math]\displaystyle{ 314 }[/math]. The following sequence achieves this:
(1, 0), (0, 1), (-1, 0), (1, 0), (-1, 0), (0, -1), (0, 1), (-1, 0), (1, 0), (1, 0), (0, -1), (-1, 0), (-1, 0), (0, -1), (1, 0), (1, 0), (-1, 0), (0, 1), (1, 0), (-1, 0), (0, -1), (-1, 0), (0, 1), (1, 0), (0, -1), (1, 0), (-1, 0), (0, 1), (1, 0), (-1, 0), (0, -1), (-1, 0), (0, 1), (0, -1), (1, 0), (1, 0), (-1, 0), (-1, 0), (1, 0), (1, 0), (0, 1), (0, 1), (-1, 0), (0, -1), (-1, 0), (1, 0), (1, 0), (-1, 0), (0, -1), (0, 1), (1, 0), (-1, 0), (1, 0), (0, -1), (0, 1), (0, -1), (-1, 0), (0, 1), (-1, 0), (1, 0), (0, -1), (-1, 0), (0, 1), (1, 0), (0, -1), (1, 0), (0, 1), (0, 1), (0, -1), (-1, 0), (1, 0), (-1, 0), (-1, 0), (1, 0), (0, 1), (1, 0), (-1, 0), (-1, 0), (1, 0), (-1, 0), (1, 0), (0, -1), (0, 1), (0, -1), (0, -1), (0, 1), (-1, 0), (0, 1), (0, -1), (1, 0), (1, 0), (-1, 0), (0, 1), (0, -1), (0, 1), (1, 0), (0, -1), (0, 1), (0, -1), (0, -1), (0, 1), (0, 1), (-1, 0), (1, 0), (-1, 0), (0, -1), (1, 0), (-1, 0), (-1, 0), (0, -1), (1, 0), (0, 1), (-1, 0), (1, 0), (1, 0), (0, -1), (-1, 0), (0, 1), (1, 0), (-1, 0), (1, 0), (-1, 0), (0, -1), (1, 0), (0, 1), (0, -1), (-1, 0), (-1, 0), (1, 0), (0, 1), (0, -1), (0, 1), (-1, 0), (1, 0), (1, 0), (0, -1), (0, 1), (-1, 0), (0, -1), (1, 0), (-1, 0), (0, 1), (0, 1), (1, 0), (-1, 0), (0, -1), (0, 1), (-1, 0), (1, 0), (0, -1), (1, 0), (-1, 0), (-1, 0), (1, 0), (0, 1), (1, 0), (0, -1), (-1, 0), (-1, 0), (1, 0), (0, -1), (0, 1), (0, 1), (-1, 0), (0, -1), (0, -1), (0, 1), (0, 1), (0, -1), (0, 1), (1, 0), (1, 0), (-1, 0), (0, -1), (-1, 0), (0, -1), (1, 0), (0, 1), (1, 0), (-1, 0), (0, -1), (-1, 0), (0, 1), (1, 0), (0, -1), (1, 0), (0, 1), (0, 1), (0, -1), (0, -1), (0, 1), (-1, 0), (-1, 0), (1, 0), (0, 1), (0, -1), (1, 0), (-1, 0), (0, -1), (0, 1), (0, -1), (-1, 0), (0, 1), (0, -1), (1, 0), (1, 0), (0, 1), (-1, 0), (0, -1), (1, 0), (0, 1), (0, 1), (-1, 0), (-1, 0), (0, -1), (1, 0), (-1, 0), (1, 0), (1, 0), (0, 1), (0, -1), (-1, 0), (0, 1), (0, -1), (0, -1), (1, 0), (0, 1), (-1, 0), (1, 0), (-1, 0), (1, 0), (0, 1), (-1, 0), (1, 0), (-1, 0), (1, 0), (-1, 0), (-1, 0), (1, 0), (1, 0), (0, -1), (-1, 0), (-1, 0), (0, -1), (1, 0), (0, 1), (0, 1), (-1, 0), (0, -1), (0, -1), (1, 0), (0, 1), (-1, 0), (1, 0), (0, 1), (1, 0), (-1, 0), (-1, 0), (1, 0), (-1, 0), (1, 0), (1, 0), (-1, 0), (0, -1), (0, -1), (0, 1), (0, 1), (0, -1), (1, 0), (-1, 0), (-1, 0), (0, 1), (0, -1), (1, 0), (0, 1), (1, 0), (-1, 0), (-1, 0), (0, -1), (0, -1), (1, 0), (0, 1), (0, -1), (-1, 0), (1, 0), (1, 0), (0, 1), (-1, 0), (0, -1), (1, 0), (-1, 0), (1, 0), (0, 1), (0, -1), (-1, 0), (0, 1), (0, 1), (0, -1), (1, 0), (0, 1), (-1, 0), (-1, 0), (1, 0), (0, -1), (0, 1), (1, 0), (-1, 0), (-1, 0), (0, -1), (1, 0), (1, 0), (0, -1), (0, 1), (0, 1)
--Alec 14:42, 9 January 2010 (UTC)
