A308529 Number of length-n binary words having exactly one nontrivial palindrome prefix.

0, 2, 4, 10, 18, 34, 62, 118, 222, 432, 834, 1642, 3230, 6406, 12702, 25298, 50386, 100566, 200716, 401022, 801230, 1601654, 3201694, 6401784, 12800378, 25597578, 51188806, 102371284, 204729938, 409447272, 818869352, 1637713546, 3275376848, 6550703506, 13101306654, 26202513022, 52404825604, 104809450870, 209618501128, 419236601774

Offset

1,2

Comments

A palindrome is nontrivial if it is of length at least 2.

Links

Table of n, a(n) for n=1..40.

Example

For n = 4 the 10 solutions are 0010, 0011, 0100, 0101, 0110 and their binary complements.

Crossrefs

Cf. A308528.

Sequence in context: A045955 A182248 A093695 * A320098 A320968 A279359

Adjacent sequences: A308526 A308527 A308528 * A308530 A308531 A308532

Keyword

nonn

Author

Jeffrey Shallit, Jun 06 2019

Extensions

a(29)-a(40) from Bert Dobbelaere, Jun 15 2019

Status

approved