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A056516

Number of primitive (period n) periodic palindromic structures using a maximum of five different symbols.

1, 1, 1, 1, 3, 4, 10, 14, 36, 50, 137, 201, 548, 854, 2417, 3839, 11060, 18001, 52599, 86471, 254982, 421989, 1252695, 2079474, 6196990, 10306747, 30795387, 51263890, 153409228, 255514354, 765389950, 1275163904, 3821990040, 6368612099, 19095299549, 31821472593

(list; graph; refs; listen; history; text; internal format)

OFFSET

0,5

COMMENTS

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

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 = 0..200

FORMULA

a(n) = Sum_{d|n} mu(d)*A056506(n/d) for n > 0.

Moebius transform of A056506. - T. D. Noe, Oct 25 2006

a(n) = Sum_{k=1..5} A285037(n, k) for n > 0. - Andrew Howroyd, Oct 01 2019

CROSSREFS

Cf. A056479, A056506, A285037.

Sequence in context: A121720 A007068 A056515 * A056517 A285042 A319719

Adjacent sequences: A056513 A056514 A056515 * A056517 A056518 A056519

KEYWORD

nonn