A330258 Number of length-n squarefree ternary words having no occurrences of either 010 or 020.

1, 3, 6, 10, 14, 22, 26, 34, 38, 44, 48, 60, 64, 64, 74, 82, 86, 100, 110, 122, 134, 150, 142, 144, 146, 150, 166, 176, 182, 198, 212, 236, 252, 264, 282, 302, 288, 280, 274, 276, 292, 312, 314, 312, 332, 356, 380, 392, 404, 428, 456, 470, 478, 492, 508, 532

Offset

0,2

References

A. Thue. Über die gegenseitige Lage gleicher Teile gewisser Zeichenreihen. Norske vid. Selsk. Skr. Mat. Nat. Kl. 1 (1912), 1-67. Reprinted in Selected Mathematical Papers of Axel Thue, T. Nagell, editor, Universitetsforlaget, Oslo, 1977, pp. 413-478.

Links

Table of n, a(n) for n=0..55.

J. Berstel, Axel Thue's papers on repetitions in words: a translation, Publications du Laboratoire de Combinatoire et d'Informatique Mathématique, Vol. 20, Université du Québec à Montréal, February 1995.

Crossrefs

Cf. A330257, A330259.

Sequence in context: A140949 A025206 A049989 * A197056 A104619 A194037

Adjacent sequences: A330255 A330256 A330257 * A330259 A330260 A330261

Keyword

nonn

Author

Jeffrey Shallit, Dec 07 2019

Status

approved