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 A330582 a(n) is the least integer k such that every ternary string of length >= k contains either a square or an n-antipower. 0
 1, 2, 4, 16, 26, 35, 54, 72, 96 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS A square is two consecutive identical blocks, such as "201201".  An n-antipower is n consecutive pairwise distinct blocks. Here are the lexicographically least strings of length a(n)-1 having neither a square nor an n-antipower: n = 3: 010 n = 4: 010201210201021 n = 5: 0102120102012102010212010 n = 6: 0102120102101201021201210201021012 n = 7: 01202120102012102120102101202120121021202101202120102 n = 8: 01020121012010210120212010201210120210201210120102101202102012101202102 n = 9: 01020121020102120210121020102120121020102101201021202101210212010210121020102120210120102120210 LINKS Gabriele Fici, Antonio Restivo, Manuel Silva, and Luca Q. Zamboni, Anti-powers in infinite words, arXiv:1606.02868 [cs.DM], 2016-2018. Gabriele Fici, Antonio Restivo, Manuel Silva, and Luca Q. Zamboni, Anti-powers in infinite words, Journal of Combinatorial Theory, Series A 157 (2018), 109-119. CROSSREFS Sequence in context: A292369 A153665 A015775 * A104258 A143904 A144797 Adjacent sequences:  A330579 A330580 A330581 * A330583 A330584 A330585 KEYWORD nonn,more AUTHOR Jeffrey Shallit, Dec 18 2019 STATUS approved

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Last modified December 8 01:25 EST 2021. Contains 349590 sequences. (Running on oeis4.)