A330259 Number of length-n ternary squarefree strings having no occurrences of either 010 or 101.

1, 3, 6, 10, 14, 20, 22, 28, 30, 36, 42, 48, 54, 62, 70, 84, 78, 82, 88, 96, 104, 112, 128, 142, 148, 168, 158, 152, 158, 170, 174, 178, 194, 210, 220, 234, 254, 264, 274, 292, 280, 282, 292, 304, 290, 296, 310, 322, 326, 340, 354, 362, 370, 384, 400, 402, 424

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..56.

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, A330258.

Sequence in context: A338335 A226185 A310071 * A024928 A330257 A079552

Adjacent sequences: A330256 A330257 A330258 * A330260 A330261 A330262

Keyword

nonn

Author

Jeffrey Shallit, Dec 07 2019

Status

approved