

A056512


Number of periodic palindromic structures of length n using exactly six different symbols.


3



0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 13, 21, 154, 266, 1488, 2646, 12857, 22827, 101485, 179487, 752647, 1323652, 5325239, 9321312, 36387288, 63436373, 242085648, 420693273, 1577871106, 2734926558, 10120485512, 17505749898, 64096921939, 110687251039, 401885424357
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OFFSET

1,12


REFERENCES

M. R. Nester (1999). Mathematical investigations of some plant interaction designs. PhD Thesis. University of Queensland, Brisbane, Australia. [See A056391 for pdf file of Chap. 2]


LINKS

Andrew Howroyd, Table of n, a(n) for n = 1..200


FORMULA

a(n) = A056507(n)  A056506(n).
Inverse Moebius transform of A056523.  Andrew Howroyd, Oct 01 2019


EXAMPLE

For example, aaabbb is not a (finite) palindrome but it is a periodic palindrome. Permuting the symbols will not change the structure.


CROSSREFS

Column k=6 of A285012.
Cf. A056475, A056506, A056507, A056523.
Sequence in context: A203854 A325448 A056523 * A158998 A122559 A132131
Adjacent sequences: A056509 A056510 A056511 * A056513 A056514 A056515


KEYWORD

nonn


AUTHOR

Marks R. Nester


EXTENSIONS

a(16)a(26) from Andrew Howroyd, Apr 07 2017
Terms a(27) and beyond from Andrew Howroyd, Oct 01 2019


STATUS

approved



