A327874 Number of length n primitive (aperiodic) palindromes with integer entries that cover an initial interval of positive integers.

1, 1, 0, 2, 2, 12, 10, 74, 72, 538, 528, 4682, 4668, 47292, 47218, 545820, 545760, 7087260, 7086710, 102247562, 102247020, 1622632496, 1622627890, 28091567594, 28091562840, 526858348368, 526858301088, 10641342969902, 10641342923148, 230283190977852, 230283190431480

Offset

0,4

Links

Andrew Howroyd, Table of n, a(n) for n = 0..200

Formula

a(n) = Sum_{d|n} mu(n/d)*A000670(ceiling(d/2)) for n > 0.

Prog

(PARI) a(n) = {if(n<1, n==0, sumdiv(n, d, moebius(n/d)*sum(k=1, ceil(d/2), k!*stirling(ceil(d/2), k, 2))))}

Crossrefs

Row sums of A327873.

Cf. A000670, A327879.

Sequence in context: A350784 A376978 A307659 * A190295 A228154 A275279

Adjacent sequences: A327871 A327872 A327873 * A327875 A327876 A327877

Keyword

nonn

Author

Andrew Howroyd, Sep 28 2019

Status

approved