A265639 Number of binary strings of length n that cannot be written as the concatenation of nontrivial powers of other strings.

2, 2, 6, 10, 26, 38, 104, 162, 394, 684, 1584, 2798, 6350, 11524, 25320, 47348, 101728, 193244, 409650, 788018, 1649198, 3207640, 6648872, 13030392, 26821720, 52867234, 108207760, 214252886, 436604050, 867366654, 1761592316, 3508334870, 7106441568, 14179665756

Offset

1,1

Links

Table of n, a(n) for n=1..34.

Formula

a(n) = 2^n - A265642(n). - Altug Alkan, Dec 20 2015

Example

For n = 4 there are 16 strings of length 4, of which 4 are powers: 0000, 1111, 0101, 1010, and 2 are the products of two powers: 0011, 1100. So a(4) = 10.

Crossrefs

Cf. A265642.

Sequence in context: A014113 A284462 A262278 * A208900 A229733 A051765

Adjacent sequences: A265636 A265637 A265638 * A265640 A265641 A265642

Keyword

nonn,base

Author

Jeffrey Shallit, Dec 11 2015

Extensions

a(17)-a(34) from Lars Blomberg, Dec 20 2015

Status

approved