

A285042


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


4



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
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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 A048155 A242342
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



