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A337056
Number of length-n binary strings such that no rotation is a palindrome.
0
0, 2, 0, 10, 0, 44, 28, 202, 252, 872, 1364, 3748, 6552, 15500, 29040, 63562, 122400, 257588, 504868, 1038520, 2054416, 4171796, 8294444, 16728580, 33349800, 67002392, 133775964, 268207012, 535920696, 1073250704, 2145452092, 4293920842, 8585610704, 17177640992, 34350563968
OFFSET
1,2
EXAMPLE
For n = 4 the 10 strings are 0001, 0010, 0100, 0101, 0111 and their binary complements.
The 5 binary palindromes are 00000, 00100, 01010, 01110, 10001, 10101, 11011, 11111. Rotating each of them around gives 32 distinct palindromes. As there are 2^5 = 32 possible binary strings of length 5 there are 32-32 = 0 binary strings such that no rotation is a palindrome. - David A. Corneth, Aug 13 2020
CROSSREFS
Cf. A057148.
Sequence in context: A368703 A345048 A151887 * A362994 A371551 A334615
KEYWORD
nonn
AUTHOR
Jeffrey Shallit, Aug 13 2020
STATUS
approved