A285042 Number of primitive (period n) periodic palindromic structures of length n using an infinite alphabet.

1, 1, 1, 1, 3, 4, 10, 14, 36, 50, 138, 202, 562, 876, 2589, 4134, 12828, 21146, 69115, 115974, 398619, 678554, 2450202, 4213596, 15939338, 27644432, 109304036, 190899270, 787013630, 1382958544, 5931819804, 10480142146, 46673246440, 82864869600, 382473261356

Offset

0,5

Comments

See A285037 for additional information. Permuting the symbols will not change the structure.

Links

Andrew Howroyd, Table of n, a(n) for n = 0..500

Formula

a(n) = Sum_{d | n} mu(n/d) * A285013(d) for n > 0.

Prog

(PARI) \\ Requires T from A285037.
seq(n)={my(A=T(n)); concat([1], vector(n, i, vecsum(A[i, ])))} \\ Andrew Howroyd, Oct 02 2019

Crossrefs

Row sums of A285037.

Cf. A285013.

Sequence in context: A056515 A056516 A056517 * A319719 A347568 A048155

Adjacent sequences: A285039 A285040 A285041 * A285043 A285044 A285045

Keyword

nonn

Author

Andrew Howroyd, Apr 08 2017

Extensions

a(0)=1 prepended and terms a(28) and beyond from Andrew Howroyd, Oct 02 2019

Status

approved