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Square-free word

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time. Apostolico and Preparata give an algorithm using suffix trees. Crochemore uses partitioning in his algorithm. Main and Lorentz provide an algorithm based on the divide-and-conquer method. A naive implementation may require
2117: 3904: 1075: 1623: 2679: 2542: 3979: 2968:. A morphism is called square-free if the image of every square-free word is square-free. A morphism is called k–square-free if the image of every square-free word of length k is square-free. 4019: 2828: 469: 1658: 1471: 507:
Since there are infinitely many square-free words over three-letter alphabets, this implies there are also infinitely many square-free words over an alphabet with more than three letters.
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Over a ternary alphabet, there are exactly 144 uniform square-free morphisms of rank 11 and no uniform square-free morphisms with a lower rank than 11.
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Every (k+1)-ary square-free word can be the output of Algorithm R2F, because on each iteration it can append any letter except for the last letter of
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one forms a new sequence in which each term is the difference of two consecutive terms of the Thue–Morse sequence. The resulting square-free word is
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Note that over a more than three-letter alphabet there are square-free words of any length without an arbitrary three-letter combination.
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Note that over a more than three-letter alphabet there are square-free words of any length without an arbitrary two-letter combination.
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Note that, if a morphism over a ternary alphabet is not uniform, then this morphism is square-free if and only if it is 5-square-free.
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Over a ternary alphabet, a square-free word of length more than 36 contains all the square-free three-letter combinations.
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Over a ternary alphabet, a square-free word of length more than 13 contains all the square-free two-letter combinations.
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Main, Michael G; Lorentz, Richard J (Sep 1984). "An O(n log n) algorithm for finding all repetitions in a string".
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One example of an infinite square-free word over an alphabet of size 3 is the word over the alphabet
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Crochemore, Max (Oct 1981). "An optimal algorithm for computing the repetitions in a word".
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Note that there exists an algorithm that can verify the square-freeness of a word of length
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over any alphabet with three or more letters. This algorithm is based on a modification of
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This can be proved by constructing a square-free word without the two-letter combination
3039: 2949:. It is possible to prove that the sequence converges to the infinite square-free word 499:. The lower bound can be found by finding a substitution that preserves square-freeness. 159: 4493: 3642:
However, there are square-free words of any length without the three-letter combination
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to it. The resulting words preserve the property of square-freeness. For example, let
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Zolotov, Boris (2015). "Another Solution to the Thue Problem of Non-Repeating Words".
4680: 4475:"The minimal density of a letter in an infinite ternary square-free word is 883/3215" 4380: 4298: 4263: 4227: 4210: 4143: 4126: 28: 4327:. Départements de mathématiques et d'informatique, Université du Québec à Montréal. 4545: 4406: 224:, there are infinitely many square-free words. It is possible to count the number 4102: 4079: 3503:
To obtain an infinite square-free words, start with any square-free word such as
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The expected number of random k-ary letters used by Algorithm R2F to construct a
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is square-free. A computer search shows that there are no 2-dimensional words
4528: 4342: 4306: 4271: 4236: 4152: 514:-ary square-free words, rounded off to 7 digits after the decimal point, for 4507:
Ochem, Pascal (2007). "Letter frequency in infinite repetition-free words".
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is not empty. Thus, a square-free word can also be defined as a word that
2700: 2356: 72: 4549: 4194: 3899:{\displaystyle \liminf _{l\to \infty }{\frac {|w_{l}|_{a}}{|w_{l}|}}} 1196:: it randomly selects letters from a k-letter alphabet to generate a 4548:; Lauve, Aaron; Reutenauer, Christophe; Saliola, Franco V. (2009). 4455: 2975:
is square-free if and only if it is 3-square-free. In other words,
1188:(random-t(w)o-free) that can generate a square-free word of length 1070:{\displaystyle t\geq 0,x_{t}=w_{{i_{1}}+{j_{1}t},{i_{2}}+{j_{2}t}}} 4551:
Combinatorics on words. Christoffel words and repetitions in words
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Shur, Arseny (2011). "Growth properties of power-free languages".
4646:; Ferenczi, SĂ©bastien; Mauduit, Christian; Siegel, Anne (eds.). 3012:
of length 3. It is possible to find a square-free morphism by
39:(a sequence of symbols) that does not contain any squares. A 4411:
Annual Symposium on Theoretical Aspects of Computer Science
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Substitutions in dynamics, arithmetics and combinatorics
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Axel Thue's papers on repetitions in words a translation
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is the longest square-free word without the combination
4211:"Optimal off-line detection of repetitions in a string" 4093:
Berthe, Valerie; Rigo, Michel, eds. (2016), "Preface",
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0121021201210120210201202120102101201021202102012021...
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time to verify the square-freeness of a word of length
1618:{\displaystyle \color {gray}w=136263163\in \Sigma _{6}} 510:
The following table shows the exact growth rate of the
4554:. CRM Monograph Series. Vol. 27. Providence, RI: 2674:{\displaystyle 1,0,-1,1,-1,0,1,0,-1,0,1,-1,1,0,-1,...} 1884: 1793: 1697: 1357: 445: 3994: 3954: 3912: 3824: 3790: 3770: 3729: 3671: 3547: 3521: 3437: 3388: 3339: 3293: 3261: 3211: 3171: 3131: 3091: 3042: 3029:
a square-free morphism with the lowest possible rank
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There exist infinitely long square-free words in any
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in an infinite ternary square-free word is equal to
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in an infinite ternary square-free word is equal to
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Carpi proves that there exists a 2-dimensional word
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The number of ternary square-free words of length n
3814:is the length of the word. The density of a letter 4013: 3973: 3925: 3898: 3806: 3776: 3752: 3715: 3569: 3533: 3482: 3403: 3369: 3323: 3276: 3241: 3186: 3146: 3106: 3054: 3000: 2919: 2884: 2855: 2822: 2769: 2740: 2673: 2537:{\displaystyle 0,1,1,0,1,0,0,1,1,0,0,1,0,1,1,0...} 2536: 2415: 2334: 2296: 2254: 2100: 2022: 1976: 1945: 1897: 1863: 1812: 1778: 1746: 1716: 1683: 1652: 1617: 1560: 1523: 1494: 1465: 1430: 1378: 1331: 1293: 1263: 1222: 1168: 1152:over a 7-letter alphabet, such that every line of 1144: 1120: 1104:over a 16-letter alphabet such that every line of 1096: 1069: 957: 900: 834: 810: 786: 747: 714: 682: 653: 483: 463: 431: 334: 245: 215: 168: 148: 98: 4097:, Cambridge University Press, pp. xi–xviii, 3974:{\displaystyle {\frac {883}{3215}}\approx 0.2747} 2779:be any square-free word starting with the letter 4014:{\displaystyle {\frac {255}{653}}\approx 0.3905} 3826: 3507:, and successively apply a square-free morphism 106:, the only square-free words are the empty word 2964:Infinite square-free words can be generated by 2823:{\displaystyle \{w_{i}\mid i\in \mathbb {N} \}} 4127:"Multidimensional unrepetitive configurations" 464:{\textstyle 1.3017597<\alpha <1.3017619} 1653:{\displaystyle \color {gray}\chi _{w}=361245} 1576:is to the right of the rightmost position of 1466:{\displaystyle \color {gray}w\in \Sigma _{k}} 8: 4209:Apostolico, A.; Preparata, F.P. (Feb 1983). 3078:the list of all square-free words of length 2817: 2790: 2735: 2717: 2410: 2386: 1424: 1394: 210: 192: 93: 81: 958:{\displaystyle {\text{gcd}}(j_{1},j_{2})=1} 4168:"Generating square-free words efficiently" 4095:Combinatorics, Words and Symbolic Dynamics 2971:Crochemore proves that a uniform morphism 2359:with three or more letters, as proved by 1431:{\displaystyle \color {gray}\{1,...,k+1\}} 4454: 4407:"Some Recent Results on Squarefree Words" 4359:(1957). "A problem on strings of beads". 4226: 4193: 4183: 4142: 3995: 3993: 3955: 3953: 3917: 3911: 3888: 3882: 3873: 3865: 3860: 3853: 3844: 3841: 3829: 3823: 3799: 3791: 3789: 3769: 3744: 3739: 3730: 3728: 3705: 3697: 3689: 3684: 3675: 3672: 3670: 3552: 3546: 3520: 3436: 3387: 3338: 3292: 3260: 3210: 3170: 3130: 3090: 3041: 2984: 2911: 2905: 2876: 2870: 2841: 2835: 2813: 2812: 2797: 2788: 2761: 2755: 2715: 2710:is defined recursively over the alphabet 2555: 2439: 2384: 2323: 2311: 2271: 2217: 2208: 2190: 2181: 2170: 2161: 2150: 2141: 2119: 2081: 1999: 1993: 1968: 1962: 1922: 1910: 1889: 1883: 1850: 1842: 1840: 1798: 1792: 1762: 1738: 1732: 1702: 1696: 1667: 1637: 1630: 1608: 1589: 1551: 1544: 1514: 1507: 1485: 1478: 1456: 1443: 1391: 1363: 1356: 1312: 1280: 1250: 1203: 1160: 1159: 1157: 1136: 1135: 1133: 1112: 1111: 1109: 1088: 1087: 1085: 1055: 1050: 1040: 1035: 1022: 1017: 1007: 1002: 1001: 988: 970: 940: 927: 915: 913: 892: 879: 866: 853: 847: 826: 825: 823: 802: 801: 799: 763: 762: 760: 733: 727: 706: 705: 703: 674: 670: 669: 666: 645: 644: 642: 476: 444: 432:{\displaystyle c(n)=\Theta (\alpha ^{n})} 420: 393: 318: 229: 190: 161: 111: 79: 3587: 3584:Letter combinations in square-free words 2431:. That is, from the Thue–Morse sequence 1524:{\displaystyle \color {gray}\Sigma _{k}} 520: 259: 4029: 3255:from the current loop (advance to next 1379:{\textstyle \color {gray}\Sigma _{k+1}} 901:{\displaystyle i_{1},i_{2},j_{1},j_{2}} 253:of ternary square-free words of length 149:{\displaystyle \epsilon ,0,1,01,10,010} 3716:{\displaystyle {\frac {|w|_{a}}{|w|}}} 3592:Extending a square-free word to avoid 1561:{\displaystyle \color {gray}\chi _{w}} 1495:{\displaystyle \color {gray}\chi _{w}} 4468: 4466: 4444: 4442: 4413:. Lecture Notes in Computer Science. 4400: 4398: 2960:Generating infinite square-free words 503:Alphabet with more than three letters 7: 4318: 4316: 4061: 4059: 4057: 1568:if the right most position of 722:is called a 2-dimensional word. Let 3515:be a square-free morphism, then as 3008:is square-free for all square-free 1905:uniformly at random append 1180:Generating finite square-free words 1161: 1137: 1113: 1089: 827: 803: 764: 707: 646: 3836: 3528: 1988:elements to the right and setting 1886: 1795: 1699: 1632: 1605: 1591: 1546: 1511: 1509: 1480: 1453: 1445: 1393: 1360: 1358: 1184:Shur proposes an algorithm called 787:{\displaystyle {\textbf {w}}(m,n)} 410: 25: 3577:is an infinite square-free word. 2830:recursively as follows: the word 1787:followed by all other letters of 4613:Algebraic combinatorics on words 3984:The maximum density of a letter 3944:The minimal density of a letter 3760:is the number of occurrences of 3082:over a ternary alphabet 2110:-ary square-free word of length 683:{\displaystyle \mathbb {N} ^{2}} 3635:Avoid three-letter combinations 3628:and its length is equal to 13. 4252:Information Processing Letters 3889: 3874: 3861: 3845: 3833: 3800: 3792: 3740: 3731: 3706: 3698: 3685: 3676: 3564: 3558: 3525: 3483:{\displaystyle h(0),h(1),h(2)} 3477: 3471: 3462: 3456: 3447: 3441: 3398: 3392: 3364: 3358: 3349: 3343: 3318: 3312: 3303: 3297: 3271: 3265: 3236: 3230: 3221: 3215: 3181: 3175: 3141: 3135: 3101: 3095: 2995: 2989: 2979:is square-free if and only if 2329: 2316: 2291: 2276: 2246: 2240: 2095: 2083: 2011: 2005: 1940: 1928: 1851: 1843: 1773: 1767: 1678: 1672: 1326: 1314: 1217: 1205: 946: 920: 781: 769: 426: 413: 404: 398: 329: 323: 240: 234: 1: 4556:American Mathematical Society 3601:Avoid two-letter combinations 3370:{\displaystyle h(2)\neq h(0)} 3324:{\displaystyle h(0)\neq h(1)} 1386:is the alphabet with letters 1169:{\displaystyle {\textbf {w}}} 1145:{\displaystyle {\textbf {w}}} 1121:{\displaystyle {\textbf {w}}} 1097:{\displaystyle {\textbf {w}}} 835:{\displaystyle {\textbf {w}}} 811:{\displaystyle {\textbf {x}}} 715:{\displaystyle {\textbf {w}}} 654:{\displaystyle {\textbf {w}}} 4509:Theoretical Computer Science 4482:Journal of Integer Sequences 4405:Berstel, Jean (April 1984). 4299:10.1016/0196-6774(84)90021-x 4264:10.1016/0020-0190(81)90024-7 4228:10.1016/0304-3975(83)90109-3 4215:Theoretical Computer Science 4172:Theoretical Computer Science 4144:10.1016/0304-3975(88)90080-1 4131:Theoretical Computer Science 4103:10.1017/cbo9781139924733.001 4080:10.1016/j.cosrev.2012.09.001 3534:{\displaystyle w\to \infty } 2416:{\displaystyle \{-1,0,+1\}} 2044:ends with a square of rank 2023:{\displaystyle \chi _{w}=a} 1946:{\displaystyle a=\chi _{w}} 518:in the range from 4 to 15: 4708: 4617:Cambridge University Press 4590:Cambridge University Press 4473:Khalyavin, Andrey (2007). 3933:is the prefix of the word 2351:Infinite square-free words 2297:{\displaystyle O(n\log n)} 1813:{\textstyle \Sigma _{k+1}} 1717:{\textstyle \Sigma _{k+1}} 388:This number is bounded by 4642:Pytheas Fogg, N. (2002). 4521:10.1016/j.tcs.2007.03.027 4373:10.1017/S0025557200236115 4185:10.1016/j.tcs.2015.07.027 3242:{\displaystyle h(1)=h(2)} 2741:{\displaystyle \{0,1,2\}} 2706:Another example found by 1977:{\displaystyle \chi _{w}} 1747:{\displaystyle \chi _{w}} 1724:uniformly at random 216:{\displaystyle \{0,1,2\}} 3657:The density of a letter 3570:{\displaystyle h^{w}(0)} 2695: 2372:First difference of the 2335:{\displaystyle O(n^{2})} 1898:{\textstyle \Sigma _{k}} 1864:{\displaystyle |w|<n} 1820:in increasing order 184:Over a ternary alphabet 62:Finite square-free words 4423:10.1007/3-540-12920-0_2 4068:Computer Science Review 3818:in an infinite word is 3753:{\displaystyle |w|_{a}} 2856:{\displaystyle w_{i+1}} 2423:obtained by taking the 1264:{\displaystyle k\geq 2} 1232:-ary square-free word. 748:{\displaystyle w_{m,n}} 526:-ary square-free words 484:{\displaystyle \alpha } 99:{\displaystyle \{0,1\}} 4692:Combinatorics on words 4586:Combinatorics on words 4323:Berstel, Jean (1994). 4125:Carpi, Arturo (1988). 4015: 3975: 3927: 3900: 3808: 3778: 3754: 3717: 3597: 3571: 3535: 3484: 3405: 3371: 3325: 3284:) 3278: 3243: 3188: 3148: 3108: 3056: 3002: 2921: 2886: 2857: 2824: 2771: 2742: 2675: 2538: 2417: 2336: 2298: 2256: 2102: 2024: 1978: 1947: 1899: 1865: 1814: 1780: 1748: 1718: 1685: 1654: 1619: 1562: 1525: 1502:is the permutation of 1496: 1467: 1432: 1380: 1341:-ary square-free word 1333: 1295: 1294:{\displaystyle n>1} 1265: 1224: 1170: 1146: 1122: 1098: 1071: 959: 902: 836: 812: 788: 749: 716: 684: 655: 485: 465: 433: 336: 247: 217: 170: 150: 100: 43:is a word of the form 4287:Journal of Algorithms 4166:Shur, Arseny (2015). 4016: 3976: 3928: 3926:{\displaystyle w_{l}} 3901: 3809: 3779: 3755: 3718: 3591: 3572: 3536: 3485: 3406: 3372: 3326: 3279: 3244: 3189: 3149: 3109: 3057: 3022:square-free_morphism 3003: 2922: 2920:{\displaystyle w_{i}} 2887: 2885:{\displaystyle w_{i}} 2858: 2825: 2772: 2770:{\displaystyle w_{1}} 2743: 2676: 2539: 2418: 2337: 2299: 2257: 2103: 2101:{\displaystyle (k+1)} 2025: 1979: 1948: 1900: 1866: 1815: 1781: 1749: 1719: 1686: 1655: 1620: 1584:. For example, 1563: 1526: 1497: 1468: 1433: 1381: 1334: 1332:{\displaystyle (k+1)} 1296: 1266: 1225: 1223:{\displaystyle (k+1)} 1171: 1147: 1123: 1099: 1072: 960: 903: 837: 813: 789: 750: 717: 685: 656: 495:and approximation by 486: 471:. The upper bound on 466: 434: 337: 248: 218: 171: 151: 101: 3992: 3952: 3910: 3822: 3788: 3768: 3727: 3669: 3545: 3519: 3435: 3404:{\displaystyle h(w)} 3386: 3337: 3291: 3277:{\displaystyle h(1)} 3259: 3209: 3187:{\displaystyle h(2)} 3169: 3147:{\displaystyle h(1)} 3129: 3107:{\displaystyle h(0)} 3089: 3040: 3001:{\displaystyle h(w)} 2983: 2966:square-free morphism 2904: 2869: 2834: 2787: 2754: 2714: 2554: 2438: 2383: 2310: 2270: 2118: 2080: 1992: 1961: 1909: 1882: 1839: 1791: 1761: 1731: 1695: 1666: 1629: 1588: 1543: 1506: 1477: 1442: 1390: 1355: 1311: 1279: 1249: 1202: 1156: 1132: 1108: 1084: 969: 912: 846: 822: 798: 759: 726: 702: 698:is an alphabet and 665: 641: 475: 443: 392: 335:{\displaystyle c(n)} 317: 246:{\displaystyle c(n)} 228: 189: 160: 110: 78: 4494:2007JIntS..10...65K 3807:{\displaystyle |w|} 3653:Density of a letter 3055:{\displaystyle k=3} 2783:. Define the words 2429:Thue–Morse sequence 2374:Thue–Morse sequence 1984:shifting the first 1438:.) (For a word 1194:entropy compression 633:2-dimensional words 527: 522:Growth rate of the 262: 169:{\displaystyle 101} 4011: 3971: 3923: 3896: 3840: 3804: 3774: 3750: 3713: 3598: 3567: 3531: 3480: 3401: 3367: 3321: 3274: 3239: 3184: 3144: 3104: 3052: 3014:brute-force search 2998: 2917: 2894:by replacing each 2882: 2853: 2820: 2767: 2738: 2671: 2534: 2413: 2332: 2294: 2252: 2098: 2020: 1974: 1943: 1895: 1861: 1810: 1776: 1744: 1714: 1681: 1650: 1649: 1615: 1614: 1558: 1557: 1521: 1520: 1492: 1491: 1463: 1462: 1428: 1427: 1376: 1375: 1329: 1291: 1261: 1220: 1166: 1142: 1118: 1094: 1067: 955: 898: 832: 808: 784: 745: 712: 680: 651: 521: 481: 461: 429: 332: 260: 243: 213: 166: 146: 96: 53:avoids the pattern 4661:978-3-540-44141-0 4626:978-0-521-18071-9 4599:978-0-521-59924-5 4565:978-0-8218-4480-9 4432:978-3-540-12920-2 4003: 3963: 3894: 3825: 3777:{\displaystyle w} 3711: 3661:in a finite word 2863:is obtained from 2223: 2196: 2176: 2156: 1779:{\displaystyle w} 1684:{\displaystyle w} 1163: 1139: 1115: 1091: 918: 829: 805: 766: 709: 648: 630: 629: 491:can be found via 386: 385: 16:(Redirected from 4699: 4687:Formal languages 4673: 4638: 4603: 4577: 4533: 4532: 4504: 4498: 4497: 4479: 4470: 4461: 4460: 4458: 4446: 4437: 4436: 4402: 4393: 4392: 4353: 4347: 4346: 4320: 4311: 4310: 4282: 4276: 4275: 4247: 4241: 4240: 4230: 4206: 4200: 4199: 4197: 4187: 4163: 4157: 4156: 4146: 4122: 4116: 4115: 4090: 4084: 4083: 4063: 4052: 4051: 4049: 4048: 4038:"A006156 - OEIS" 4034: 4020: 4018: 4017: 4012: 4004: 3996: 3987: 3980: 3978: 3977: 3972: 3964: 3956: 3947: 3940: 3936: 3932: 3930: 3929: 3924: 3922: 3921: 3905: 3903: 3902: 3897: 3895: 3893: 3892: 3887: 3886: 3877: 3871: 3870: 3869: 3864: 3858: 3857: 3848: 3842: 3839: 3817: 3813: 3811: 3810: 3805: 3803: 3795: 3783: 3781: 3780: 3775: 3763: 3759: 3757: 3756: 3751: 3749: 3748: 3743: 3734: 3722: 3720: 3719: 3714: 3712: 3710: 3709: 3701: 3695: 3694: 3693: 3688: 3679: 3673: 3664: 3660: 3645: 3627: 3622: 3619: 3616: 3611: 3595: 3576: 3574: 3573: 3568: 3557: 3556: 3540: 3538: 3537: 3532: 3514: 3510: 3506: 3497: 3493: 3489: 3487: 3486: 3481: 3425: 3421: 3418:all square-free 3410: 3408: 3407: 3402: 3376: 3374: 3373: 3368: 3330: 3328: 3327: 3322: 3283: 3281: 3280: 3275: 3248: 3246: 3245: 3240: 3193: 3191: 3190: 3185: 3153: 3151: 3150: 3145: 3113: 3111: 3110: 3105: 3081: 3061: 3059: 3058: 3053: 3032: 3011: 3007: 3005: 3004: 2999: 2978: 2974: 2955: 2948: 2944: 2940: 2936: 2932: 2928: 2926: 2924: 2923: 2918: 2916: 2915: 2897: 2893: 2891: 2889: 2888: 2883: 2881: 2880: 2862: 2860: 2859: 2854: 2852: 2851: 2829: 2827: 2826: 2821: 2816: 2802: 2801: 2782: 2778: 2776: 2774: 2773: 2768: 2766: 2765: 2747: 2745: 2744: 2739: 2686: 2680: 2678: 2677: 2672: 2543: 2541: 2540: 2535: 2425:first difference 2422: 2420: 2419: 2414: 2346: 2341: 2339: 2338: 2333: 2328: 2327: 2303: 2301: 2300: 2295: 2265: 2261: 2259: 2258: 2253: 2233: 2229: 2228: 2224: 2222: 2221: 2209: 2197: 2195: 2194: 2182: 2177: 2175: 2174: 2162: 2157: 2155: 2154: 2142: 2113: 2109: 2107: 2105: 2104: 2099: 2070: 2064: 2058: 2054: 2051:delete the last 2047: 2043: 2037: 2033: 2029: 2027: 2026: 2021: 2004: 2003: 1987: 1983: 1981: 1980: 1975: 1973: 1972: 1956: 1952: 1950: 1949: 1944: 1927: 1926: 1904: 1902: 1901: 1896: 1894: 1893: 1877: 1870: 1868: 1867: 1862: 1854: 1846: 1827: 1819: 1817: 1816: 1811: 1809: 1808: 1785: 1783: 1782: 1777: 1753: 1751: 1750: 1745: 1743: 1742: 1723: 1721: 1720: 1715: 1713: 1712: 1690: 1688: 1687: 1682: 1661: 1659: 1657: 1656: 1651: 1642: 1641: 1624: 1622: 1621: 1616: 1613: 1612: 1583: 1579: 1575: 1571: 1567: 1565: 1564: 1559: 1556: 1555: 1538: 1534: 1530: 1528: 1527: 1522: 1519: 1518: 1501: 1499: 1498: 1493: 1490: 1489: 1472: 1470: 1469: 1464: 1461: 1460: 1437: 1435: 1434: 1429: 1385: 1383: 1382: 1377: 1374: 1373: 1348: 1344: 1340: 1338: 1336: 1335: 1330: 1300: 1298: 1297: 1292: 1270: 1268: 1267: 1262: 1231: 1229: 1227: 1226: 1221: 1191: 1176:is square-free. 1175: 1173: 1172: 1167: 1165: 1164: 1151: 1149: 1148: 1143: 1141: 1140: 1127: 1125: 1124: 1119: 1117: 1116: 1103: 1101: 1100: 1095: 1093: 1092: 1076: 1074: 1073: 1068: 1066: 1065: 1064: 1060: 1059: 1046: 1045: 1044: 1031: 1027: 1026: 1013: 1012: 1011: 993: 992: 964: 962: 961: 956: 945: 944: 932: 931: 919: 916: 907: 905: 904: 899: 897: 896: 884: 883: 871: 870: 858: 857: 842:if there exists 841: 839: 838: 833: 831: 830: 817: 815: 814: 809: 807: 806: 793: 791: 790: 785: 768: 767: 754: 752: 751: 746: 744: 743: 721: 719: 718: 713: 711: 710: 697: 693: 689: 687: 686: 681: 679: 678: 673: 660: 658: 657: 652: 650: 649: 584: 534: 528: 525: 517: 513: 490: 488: 487: 482: 470: 468: 467: 462: 438: 436: 435: 430: 425: 424: 343: 341: 339: 338: 333: 268: 263: 256: 252: 250: 249: 244: 222: 220: 219: 214: 180:Ternary alphabet 175: 173: 172: 167: 155: 153: 152: 147: 105: 103: 102: 97: 57: 50: 46: 33:square-free word 21: 4707: 4706: 4702: 4701: 4700: 4698: 4697: 4696: 4677: 4676: 4662: 4652:Springer-Verlag 4644:BerthĂ©, ValĂ©rie 4641: 4627: 4607: 4600: 4580: 4566: 4544: 4541: 4536: 4506: 4505: 4501: 4477: 4472: 4471: 4464: 4448: 4447: 4440: 4433: 4404: 4403: 4396: 4355: 4354: 4350: 4335: 4322: 4321: 4314: 4284: 4283: 4279: 4249: 4248: 4244: 4208: 4207: 4203: 4165: 4164: 4160: 4124: 4123: 4119: 4113: 4092: 4091: 4087: 4065: 4064: 4055: 4046: 4044: 4036: 4035: 4031: 4027: 3990: 3989: 3985: 3950: 3949: 3945: 3938: 3934: 3913: 3908: 3907: 3878: 3872: 3859: 3849: 3843: 3820: 3819: 3815: 3786: 3785: 3766: 3765: 3761: 3738: 3725: 3724: 3696: 3683: 3674: 3667: 3666: 3665:is defined as 3662: 3658: 3655: 3643: 3637: 3625: 3620: 3617: 3614: 3612:. As a result, 3609: 3603: 3593: 3586: 3548: 3543: 3542: 3517: 3516: 3512: 3508: 3504: 3498: 3495: 3491: 3433: 3432: 3423: 3419: 3384: 3383: 3335: 3334: 3289: 3288: 3257: 3256: 3207: 3206: 3167: 3166: 3127: 3126: 3087: 3086: 3079: 3038: 3037: 3030: 3009: 2981: 2980: 2976: 2972: 2962: 2953: 2946: 2942: 2938: 2934: 2930: 2907: 2902: 2901: 2899: 2895: 2872: 2867: 2866: 2864: 2837: 2832: 2831: 2793: 2785: 2784: 2780: 2757: 2752: 2751: 2749: 2712: 2711: 2704: 2682: 2552: 2551: 2436: 2435: 2381: 2380: 2377: 2369: 2353: 2344: 2319: 2308: 2307: 2268: 2267: 2263: 2213: 2204: 2186: 2166: 2146: 2134: 2130: 2116: 2115: 2111: 2078: 2077: 2075: 2068: 2065: 2062: 2056: 2052: 2045: 2041: 2035: 2031: 1995: 1990: 1989: 1985: 1964: 1959: 1958: 1954: 1918: 1907: 1906: 1885: 1880: 1879: 1875: 1837: 1836: 1825: 1794: 1789: 1788: 1759: 1758: 1734: 1729: 1728: 1698: 1693: 1692: 1664: 1663: 1633: 1627: 1626: 1604: 1586: 1585: 1581: 1577: 1573: 1569: 1547: 1541: 1540: 1536: 1532: 1510: 1504: 1503: 1481: 1475: 1474: 1452: 1440: 1439: 1388: 1387: 1359: 1353: 1352: 1350: 1346: 1342: 1309: 1308: 1306: 1277: 1276: 1247: 1246: 1200: 1199: 1197: 1189: 1182: 1154: 1153: 1130: 1129: 1106: 1105: 1082: 1081: 1051: 1036: 1018: 1003: 997: 984: 967: 966: 936: 923: 910: 909: 888: 875: 862: 849: 844: 843: 820: 819: 796: 795: 757: 756: 729: 724: 723: 700: 699: 695: 691: 668: 663: 662: 639: 638: 637:Consider a map 635: 582: 581:alphabet size ( 532: 531:alphabet size ( 523: 515: 511: 505: 473: 472: 441: 440: 416: 390: 389: 315: 314: 312: 266: 254: 226: 225: 187: 186: 182: 158: 157: 108: 107: 76: 75: 69: 67:Binary alphabet 64: 55: 48: 44: 23: 22: 18:Squarefree word 15: 12: 11: 5: 4705: 4703: 4695: 4694: 4689: 4679: 4678: 4675: 4674: 4660: 4639: 4625: 4605: 4598: 4578: 4564: 4540: 4537: 4535: 4534: 4515:(3): 388–392. 4499: 4462: 4438: 4431: 4394: 4348: 4334:978-2892761405 4333: 4312: 4293:(3): 422–432. 4277: 4258:(5): 244–250. 4242: 4221:(3): 297–315. 4201: 4158: 4137:(2): 233–241. 4117: 4111: 4085: 4074:(5–6): 28–43. 4053: 4028: 4026: 4023: 4010: 4007: 4002: 3999: 3970: 3967: 3962: 3959: 3920: 3916: 3891: 3885: 3881: 3876: 3868: 3863: 3856: 3852: 3847: 3838: 3835: 3832: 3828: 3827:lim inf 3802: 3798: 3794: 3773: 3747: 3742: 3737: 3733: 3708: 3704: 3700: 3692: 3687: 3682: 3678: 3654: 3651: 3636: 3633: 3602: 3599: 3585: 3582: 3566: 3563: 3560: 3555: 3551: 3530: 3527: 3524: 3479: 3476: 3473: 3470: 3467: 3464: 3461: 3458: 3455: 3452: 3449: 3446: 3443: 3440: 3400: 3397: 3394: 3391: 3366: 3363: 3360: 3357: 3354: 3351: 3348: 3345: 3342: 3320: 3317: 3314: 3311: 3308: 3305: 3302: 3299: 3296: 3273: 3270: 3267: 3264: 3238: 3235: 3232: 3229: 3226: 3223: 3220: 3217: 3214: 3183: 3180: 3177: 3174: 3143: 3140: 3137: 3134: 3103: 3100: 3097: 3094: 3051: 3048: 3045: 3018: 2997: 2994: 2991: 2988: 2961: 2958: 2957: 2956: 2914: 2910: 2879: 2875: 2850: 2847: 2844: 2840: 2819: 2815: 2811: 2808: 2805: 2800: 2796: 2792: 2764: 2760: 2737: 2734: 2731: 2728: 2725: 2722: 2719: 2703: 2694: 2693: 2692: 2670: 2667: 2664: 2661: 2658: 2655: 2652: 2649: 2646: 2643: 2640: 2637: 2634: 2631: 2628: 2625: 2622: 2619: 2616: 2613: 2610: 2607: 2604: 2601: 2598: 2595: 2592: 2589: 2586: 2583: 2580: 2577: 2574: 2571: 2568: 2565: 2562: 2559: 2545: 2544: 2533: 2530: 2527: 2524: 2521: 2518: 2515: 2512: 2509: 2506: 2503: 2500: 2497: 2494: 2491: 2488: 2485: 2482: 2479: 2476: 2473: 2470: 2467: 2464: 2461: 2458: 2455: 2452: 2449: 2446: 2443: 2412: 2409: 2406: 2403: 2400: 2397: 2394: 2391: 2388: 2376: 2370: 2368: 2365: 2352: 2349: 2331: 2326: 2322: 2318: 2315: 2293: 2290: 2287: 2284: 2281: 2278: 2275: 2251: 2248: 2245: 2242: 2239: 2236: 2232: 2227: 2220: 2216: 2212: 2207: 2203: 2200: 2193: 2189: 2185: 2180: 2173: 2169: 2165: 2160: 2153: 2149: 2145: 2140: 2137: 2133: 2129: 2126: 2123: 2097: 2094: 2091: 2088: 2085: 2019: 2016: 2013: 2010: 2007: 2002: 1998: 1971: 1967: 1953:to the end of 1942: 1939: 1936: 1933: 1930: 1925: 1921: 1917: 1914: 1892: 1888: 1860: 1857: 1853: 1849: 1845: 1828:of iterations 1807: 1804: 1801: 1797: 1775: 1772: 1769: 1766: 1741: 1737: 1711: 1708: 1705: 1701: 1680: 1677: 1674: 1671: 1648: 1645: 1640: 1636: 1611: 1607: 1603: 1600: 1597: 1594: 1554: 1550: 1517: 1513: 1488: 1484: 1459: 1455: 1451: 1448: 1426: 1423: 1420: 1417: 1414: 1411: 1408: 1405: 1402: 1399: 1396: 1372: 1369: 1366: 1362: 1328: 1325: 1322: 1319: 1316: 1290: 1287: 1284: 1260: 1257: 1254: 1245:alphabet size 1234: 1219: 1216: 1213: 1210: 1207: 1181: 1178: 1063: 1058: 1054: 1049: 1043: 1039: 1034: 1030: 1025: 1021: 1016: 1010: 1006: 1000: 996: 991: 987: 983: 980: 977: 974: 954: 951: 948: 943: 939: 935: 930: 926: 922: 895: 891: 887: 882: 878: 874: 869: 865: 861: 856: 852: 783: 780: 777: 774: 771: 742: 739: 736: 732: 677: 672: 634: 631: 628: 627: 624: 621: 618: 615: 612: 609: 605: 604: 601: 598: 595: 592: 589: 586: 578: 577: 574: 571: 568: 565: 562: 559: 555: 554: 551: 548: 545: 542: 539: 536: 504: 501: 493:Fekete's Lemma 480: 460: 457: 454: 451: 448: 428: 423: 419: 415: 412: 409: 406: 403: 400: 397: 384: 383: 380: 377: 374: 371: 368: 365: 362: 359: 356: 353: 350: 347: 344: 331: 328: 325: 322: 309: 308: 305: 302: 299: 296: 293: 290: 287: 284: 281: 278: 275: 272: 269: 242: 239: 236: 233: 212: 209: 206: 203: 200: 197: 194: 181: 178: 165: 145: 142: 139: 136: 133: 130: 127: 124: 121: 118: 115: 95: 92: 89: 86: 83: 71:Over a binary 68: 65: 63: 60: 24: 14: 13: 10: 9: 6: 4: 3: 2: 4704: 4693: 4690: 4688: 4685: 4684: 4682: 4671: 4667: 4663: 4657: 4653: 4649: 4645: 4640: 4636: 4632: 4628: 4622: 4618: 4614: 4610: 4606: 4601: 4595: 4591: 4588:. Cambridge: 4587: 4583: 4579: 4575: 4571: 4567: 4561: 4557: 4553: 4552: 4547: 4546:Berstel, Jean 4543: 4542: 4538: 4530: 4526: 4522: 4518: 4514: 4510: 4503: 4500: 4495: 4491: 4487: 4483: 4476: 4469: 4467: 4463: 4457: 4452: 4445: 4443: 4439: 4434: 4428: 4424: 4420: 4416: 4412: 4408: 4401: 4399: 4395: 4390: 4386: 4382: 4378: 4374: 4370: 4366: 4362: 4358: 4352: 4349: 4344: 4340: 4336: 4330: 4326: 4319: 4317: 4313: 4308: 4304: 4300: 4296: 4292: 4288: 4281: 4278: 4273: 4269: 4265: 4261: 4257: 4253: 4246: 4243: 4238: 4234: 4229: 4224: 4220: 4216: 4212: 4205: 4202: 4196: 4191: 4186: 4181: 4177: 4173: 4169: 4162: 4159: 4154: 4150: 4145: 4140: 4136: 4132: 4128: 4121: 4118: 4114: 4112:9781139924733 4108: 4104: 4100: 4096: 4089: 4086: 4081: 4077: 4073: 4069: 4062: 4060: 4058: 4054: 4043: 4039: 4033: 4030: 4024: 4022: 4008: 4005: 4000: 3997: 3982: 3968: 3965: 3960: 3957: 3942: 3918: 3914: 3883: 3879: 3866: 3854: 3850: 3830: 3796: 3771: 3745: 3735: 3702: 3690: 3680: 3652: 3650: 3647: 3640: 3634: 3632: 3629: 3623: 3606: 3600: 3590: 3583: 3581: 3578: 3561: 3553: 3549: 3522: 3501: 3474: 3468: 3465: 3459: 3453: 3450: 3444: 3438: 3431: 3428: 3417: 3413: 3395: 3389: 3382: 3379: 3361: 3355: 3352: 3346: 3340: 3333: 3315: 3309: 3306: 3300: 3294: 3287: 3268: 3262: 3254: 3251: 3233: 3227: 3224: 3218: 3212: 3205: 3202: 3199: 3196: 3178: 3172: 3165: 3162: 3159: 3156: 3138: 3132: 3125: 3122: 3119: 3116: 3098: 3092: 3085: 3077: 3074: 3071: 3068: 3064: 3049: 3046: 3043: 3036: 3028: 3025: 3021: 3017: 3015: 2992: 2986: 2969: 2967: 2959: 2952: 2951: 2950: 2947:2010210120102 2939:1202102012021 2931:0121021201210 2912: 2908: 2877: 2873: 2848: 2845: 2842: 2838: 2809: 2806: 2803: 2798: 2794: 2762: 2758: 2732: 2729: 2726: 2723: 2720: 2709: 2702: 2698: 2690: 2685: 2668: 2665: 2662: 2659: 2656: 2653: 2650: 2647: 2644: 2641: 2638: 2635: 2632: 2629: 2626: 2623: 2620: 2617: 2614: 2611: 2608: 2605: 2602: 2599: 2596: 2593: 2590: 2587: 2584: 2581: 2578: 2575: 2572: 2569: 2566: 2563: 2560: 2557: 2550: 2549: 2548: 2531: 2528: 2525: 2522: 2519: 2516: 2513: 2510: 2507: 2504: 2501: 2498: 2495: 2492: 2489: 2486: 2483: 2480: 2477: 2474: 2471: 2468: 2465: 2462: 2459: 2456: 2453: 2450: 2447: 2444: 2441: 2434: 2433: 2432: 2430: 2426: 2407: 2404: 2401: 2398: 2395: 2392: 2389: 2375: 2371: 2366: 2364: 2362: 2358: 2350: 2348: 2342: 2324: 2320: 2313: 2288: 2285: 2282: 2279: 2273: 2249: 2243: 2237: 2234: 2230: 2225: 2218: 2214: 2210: 2205: 2201: 2198: 2191: 2187: 2183: 2178: 2171: 2167: 2163: 2158: 2151: 2147: 2143: 2138: 2135: 2131: 2127: 2124: 2121: 2092: 2089: 2086: 2072: 2061: 2050: 2040: 2017: 2014: 2008: 2000: 1996: 1969: 1965: 1937: 1934: 1931: 1923: 1919: 1915: 1912: 1890: 1873: 1858: 1855: 1847: 1835: 1831: 1823: 1805: 1802: 1799: 1786: 1770: 1764: 1756: 1739: 1735: 1727: 1709: 1706: 1703: 1675: 1669: 1646: 1643: 1638: 1634: 1609: 1601: 1598: 1595: 1592: 1552: 1548: 1515: 1486: 1482: 1457: 1449: 1446: 1421: 1418: 1415: 1412: 1409: 1406: 1403: 1400: 1397: 1370: 1367: 1364: 1323: 1320: 1317: 1304: 1301: 1288: 1285: 1282: 1273: 1258: 1255: 1252: 1244: 1241: 1237: 1233: 1214: 1211: 1208: 1195: 1187: 1179: 1177: 1078: 1061: 1056: 1052: 1047: 1041: 1037: 1032: 1028: 1023: 1019: 1014: 1008: 1004: 998: 994: 989: 985: 981: 978: 975: 972: 952: 949: 941: 937: 933: 928: 924: 893: 889: 885: 880: 876: 872: 867: 863: 859: 854: 850: 818:is a line of 778: 775: 772: 755:be the entry 740: 737: 734: 730: 675: 632: 625: 622: 619: 616: 613: 610: 607: 606: 602: 599: 596: 593: 590: 587: 580: 579: 575: 572: 569: 566: 563: 560: 557: 556: 552: 549: 546: 543: 540: 537: 530: 529: 519: 508: 502: 500: 498: 494: 478: 458: 455: 452: 449: 446: 421: 417: 407: 401: 395: 381: 378: 375: 372: 369: 366: 363: 360: 357: 354: 351: 348: 345: 326: 320: 311: 310: 306: 303: 300: 297: 294: 291: 288: 285: 282: 279: 276: 273: 270: 265: 264: 258: 237: 231: 223: 207: 204: 201: 198: 195: 179: 177: 163: 143: 140: 137: 134: 131: 128: 125: 122: 119: 116: 113: 90: 87: 84: 74: 66: 61: 59: 54: 42: 38: 34: 30: 29:combinatorics 19: 4647: 4612: 4609:Lothaire, M. 4585: 4582:Lothaire, M. 4550: 4512: 4508: 4502: 4485: 4481: 4414: 4410: 4364: 4360: 4351: 4324: 4290: 4286: 4280: 4255: 4251: 4245: 4218: 4214: 4204: 4175: 4171: 4161: 4134: 4130: 4120: 4094: 4088: 4071: 4067: 4045:. Retrieved 4041: 4032: 3983: 3943: 3656: 3648: 3641: 3638: 3630: 3613: 3607: 3604: 3579: 3502: 3499: 3429: 3426: 3415: 3414:square-free 3411: 3380: 3377: 3331: 3285: 3252: 3249: 3203: 3200: 3197: 3194: 3163: 3160: 3157: 3154: 3123: 3120: 3117: 3114: 3083: 3075: 3072: 3069: 3066: 3062: 3034: 3026: 3023: 3019: 2970: 2965: 2963: 2705: 2546: 2378: 2354: 2306: 2073: 2066: 2059: 2048: 2038: 1871: 1833: 1829: 1821: 1757: 1754: 1725: 1302: 1275: 1274:word length 1271: 1242: 1239: 1235: 1185: 1183: 1079: 636: 608:growth rate 558:growth rate 509: 506: 387: 185: 183: 70: 40: 32: 26: 4367:: 277–278. 4195:10995/92700 2941:, and each 2055:letters of 1824:the number 1351:(Note that 626:13.9282035 623:12.9226167 620:11.9160804 617:10.9083279 4681:Categories 4670:1014.11015 4635:1221.68183 4574:1161.68043 4539:References 4456:1505.00019 4389:0079.01101 4047:2019-03-28 3937:of length 3490:increment 3422:of length 3198:k_sf_words 3158:k_sf_words 3118:k_sf_words 3073:k_sf_words 2708:John Leech 2681:(sequence 2030:increment 1531:such that 1345:of length 965:, and for 908:such that 614:9.8989813 611:8.8874856 576:7.8729902 573:6.8541173 570:5.8284661 567:4.7914069 564:3.7325386 561:2.6215080 4529:0304-3975 4417:: 14–25. 4381:126406225 4361:Math. Gaz 4357:Leech, J. 4343:494791187 4307:0196-6774 4272:0020-0190 4237:0304-3975 4178:: 67–72. 4153:0304-3975 4006:≈ 3966:≈ 3837:∞ 3834:→ 3529:∞ 3526:→ 3353:≠ 3307:≠ 3020:algorithm 2810:∈ 2804:∣ 2654:− 2633:− 2612:− 2585:− 2570:− 2390:− 2361:Axel Thue 2286:⁡ 1997:χ 1966:χ 1920:χ 1887:Σ 1796:Σ 1736:χ 1700:Σ 1635:χ 1606:Σ 1602:∈ 1599:136263163 1549:χ 1535:precedes 1512:Σ 1483:χ 1454:Σ 1450:∈ 1361:Σ 1256:≥ 1236:algorithm 976:≥ 794:. A word 479:α 459:1.3017619 453:α 447:1.3017597 418:α 411:Θ 114:ϵ 4611:(2011). 4584:(1997). 4488:(2): 3. 4042:oeis.org 3164:for each 3124:for each 3084:for each 2701:morphism 2367:Examples 2357:alphabet 694:, where 497:automata 439:, where 73:alphabet 47:, where 4490:Bibcode 3027:output: 2933:, each 2927:⁠ 2900:⁠ 2892:⁠ 2865:⁠ 2777:⁠ 2750:⁠ 2748:. Let 2687:in the 2684:A029883 2427:of the 2108:⁠ 2076:⁠ 1957:update 1874:choose 1662:choose 1339:⁠ 1307:⁠ 1303:output: 1230:⁠ 1198:⁠ 342:⁠ 313:⁠ 4668:  4658:  4633:  4623:  4596:  4572:  4562:  4527:  4429:  4387:  4379:  4341:  4331:  4305:  4270:  4235:  4151:  4109:  4009:0.3905 3969:0.2747 3906:where 3723:where 3430:return 3033:. 2060:return 1832:0 1647:361245 1349:. 1243:input: 156:, and 41:square 4478:(PDF) 4451:arXiv 4377:S2CID 4025:Notes 3621:cbaca 3253:break 3065:True 3063:while 2945:with 2937:with 2929:with 2697:Leech 1834:while 661:from 35:is a 4656:ISBN 4621:ISBN 4594:ISBN 4560:ISBN 4525:ISSN 4427:ISBN 4339:OCLC 4329:ISBN 4303:ISSN 4268:ISSN 4233:ISSN 4149:ISSN 4107:ISBN 3961:3215 3784:and 3618:cbca 3615:bcba 3427:then 3378:then 3250:then 2689:OEIS 2532:0... 2049:then 1856:< 1625:has 1286:> 1238:R2F 456:< 450:< 382:264 379:204 376:144 373:108 37:word 31:, a 4666:Zbl 4631:Zbl 4570:Zbl 4517:doi 4513:380 4419:doi 4415:166 4385:Zbl 4369:doi 4295:doi 4260:doi 4223:doi 4190:hdl 4180:doi 4176:601 4139:doi 4099:doi 4076:doi 4001:653 3998:255 3958:883 3764:in 3644:aba 3494:by 3416:for 3332:and 3070:set 3035:set 2898:in 2699:'s 2283:log 2266:in 2034:by 1878:in 1822:set 1726:set 1691:in 1580:in 1572:in 1539:in 1186:R2F 917:gcd 690:to 603:15 600:14 597:13 594:12 591:11 588:10 370:78 367:60 364:42 361:30 358:18 355:12 307:12 304:11 301:10 164:101 144:010 27:In 4683:: 4664:. 4654:. 4629:. 4619:. 4592:. 4568:. 4558:. 4523:. 4511:. 4486:10 4484:. 4480:. 4465:^ 4441:^ 4425:. 4409:. 4397:^ 4383:. 4375:. 4365:41 4363:. 4337:. 4315:^ 4301:. 4289:. 4266:. 4256:12 4254:. 4231:. 4219:22 4217:. 4213:. 4188:. 4174:. 4170:. 4147:. 4135:56 4133:. 4129:. 4105:, 4070:. 4056:^ 4040:. 4021:. 3981:. 3941:. 3646:. 3626:ab 3610:ab 3594:ab 3541:, 3412:is 3381:if 3286:if 3204:if 3201:do 3195:in 3161:do 3155:in 3121:do 3115:in 3076:to 3067:do 3024:is 3016:. 2691:). 2363:. 2347:. 2114:is 2071:. 2039:if 1872:do 1830:to 1755:to 1660:.) 1473:, 1305:a 1240:is 1077:. 585:) 553:9 550:8 547:7 544:6 541:5 538:4 535:) 352:6 349:3 346:1 298:9 295:8 292:7 289:6 286:5 283:4 280:3 277:2 274:1 271:0 257:. 176:. 138:10 132:01 58:. 56:XX 45:XX 4672:. 4637:. 4604:. 4602:. 4576:. 4531:. 4519:: 4496:. 4492:: 4459:. 4453:: 4435:. 4421:: 4391:. 4371:: 4345:. 4309:. 4297:: 4291:5 4274:. 4262:: 4239:. 4225:: 4198:. 4192:: 4182:: 4155:. 4141:: 4101:: 4082:. 4078:: 4072:6 4050:. 3986:a 3946:a 3939:l 3935:w 3919:l 3915:w 3890:| 3884:l 3880:w 3875:| 3867:a 3862:| 3855:l 3851:w 3846:| 3831:l 3816:a 3801:| 3797:w 3793:| 3772:w 3762:a 3746:a 3741:| 3736:w 3732:| 3707:| 3703:w 3699:| 3691:a 3686:| 3681:w 3677:| 3663:w 3659:a 3596:. 3565:) 3562:0 3559:( 3554:w 3550:h 3523:w 3513:h 3509:h 3505:0 3496:1 3492:k 3478:) 3475:2 3472:( 3469:h 3466:, 3463:) 3460:1 3457:( 3454:h 3451:, 3448:) 3445:0 3442:( 3439:h 3424:3 3420:w 3399:) 3396:w 3393:( 3390:h 3365:) 3362:0 3359:( 3356:h 3350:) 3347:2 3344:( 3341:h 3319:) 3316:1 3313:( 3310:h 3304:) 3301:0 3298:( 3295:h 3272:) 3269:1 3266:( 3263:h 3237:) 3234:2 3231:( 3228:h 3225:= 3222:) 3219:1 3216:( 3213:h 3182:) 3179:2 3176:( 3173:h 3142:) 3139:1 3136:( 3133:h 3102:) 3099:0 3096:( 3093:h 3080:k 3050:3 3047:= 3044:k 3031:k 3010:w 2996:) 2993:w 2990:( 2987:h 2977:h 2973:h 2943:2 2935:1 2913:i 2909:w 2896:0 2878:i 2874:w 2849:1 2846:+ 2843:i 2839:w 2818:} 2814:N 2807:i 2799:i 2795:w 2791:{ 2781:0 2763:1 2759:w 2736:} 2733:2 2730:, 2727:1 2724:, 2721:0 2718:{ 2669:. 2666:. 2663:. 2660:, 2657:1 2651:, 2648:0 2645:, 2642:1 2639:, 2636:1 2630:, 2627:1 2624:, 2621:0 2618:, 2615:1 2609:, 2606:0 2603:, 2600:1 2597:, 2594:0 2591:, 2588:1 2582:, 2579:1 2576:, 2573:1 2567:, 2564:0 2561:, 2558:1 2529:, 2526:1 2523:, 2520:1 2517:, 2514:0 2511:, 2508:1 2505:, 2502:0 2499:, 2496:0 2493:, 2490:1 2487:, 2484:1 2481:, 2478:0 2475:, 2472:0 2469:, 2466:1 2463:, 2460:0 2457:, 2454:1 2451:, 2448:1 2445:, 2442:0 2411:} 2408:1 2405:+ 2402:, 2399:0 2396:, 2393:1 2387:{ 2345:n 2330:) 2325:2 2321:n 2317:( 2314:O 2292:) 2289:n 2280:n 2277:( 2274:O 2264:n 2250:. 2247:) 2244:1 2241:( 2238:O 2235:+ 2231:) 2226:) 2219:5 2215:k 2211:1 2206:( 2202:O 2199:+ 2192:4 2188:k 2184:4 2179:+ 2172:3 2168:k 2164:1 2159:+ 2152:2 2148:k 2144:2 2139:+ 2136:1 2132:( 2128:n 2125:= 2122:N 2112:n 2096:) 2093:1 2090:+ 2087:k 2084:( 2069:w 2063:w 2057:w 2053:r 2046:r 2042:w 2036:1 2032:N 2018:a 2015:= 2012:] 2009:1 2006:[ 2001:w 1986:j 1970:w 1955:w 1941:] 1938:1 1935:+ 1932:j 1929:[ 1924:w 1916:= 1913:a 1891:k 1876:j 1859:n 1852:| 1848:w 1844:| 1826:N 1806:1 1803:+ 1800:k 1774:] 1771:1 1768:[ 1765:w 1740:w 1710:1 1707:+ 1704:k 1679:] 1676:1 1673:[ 1670:w 1644:= 1639:w 1610:6 1596:= 1593:w 1582:w 1578:b 1574:w 1570:a 1553:w 1537:b 1533:a 1516:k 1487:w 1458:k 1447:w 1425:} 1422:1 1419:+ 1416:k 1413:, 1410:. 1407:. 1404:. 1401:, 1398:1 1395:{ 1371:1 1368:+ 1365:k 1347:n 1343:w 1327:) 1324:1 1321:+ 1318:k 1315:( 1289:1 1283:n 1272:, 1259:2 1253:k 1218:) 1215:1 1212:+ 1209:k 1206:( 1190:n 1162:w 1138:w 1114:w 1090:w 1062:t 1057:2 1053:j 1048:+ 1042:2 1038:i 1033:, 1029:t 1024:1 1020:j 1015:+ 1009:1 1005:i 999:w 995:= 990:t 986:x 982:, 979:0 973:t 953:1 950:= 947:) 942:2 938:j 934:, 929:1 925:j 921:( 894:2 890:j 886:, 881:1 877:j 873:, 868:2 864:i 860:, 855:1 851:i 828:w 804:x 782:) 779:n 776:, 773:m 770:( 765:w 741:n 738:, 735:m 731:w 708:w 696:A 692:A 676:2 671:N 647:w 583:k 533:k 524:k 516:k 512:k 427:) 422:n 414:( 408:= 405:) 402:n 399:( 396:c 330:) 327:n 324:( 321:c 267:n 255:n 241:) 238:n 235:( 232:c 211:} 208:2 205:, 202:1 199:, 196:0 193:{ 141:, 135:, 129:, 126:1 123:, 120:0 117:, 94:} 91:1 88:, 85:0 82:{ 49:X 20:)

Index

Squarefree word
combinatorics
word
avoids the pattern
alphabet
Fekete's Lemma
automata
entropy compression
alphabet
Axel Thue
Thue–Morse sequence
first difference
Thue–Morse sequence
A029883
OEIS
Leech
morphism
John Leech
brute-force search

"A006156 - OEIS"



doi
10.1016/j.cosrev.2012.09.001
doi
10.1017/cbo9781139924733.001
ISBN
9781139924733

Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.

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