A056478 Number of primitive (aperiodic) palindromic structures using a maximum of four different symbols.

1, 1, 0, 1, 1, 4, 3, 14, 13, 49, 46, 186, 181, 714, 700, 2789, 2780, 11050, 10997, 43946, 43895, 175259, 175088, 700074, 699875, 2798246, 2797536, 11188856, 11188191, 44747434, 44744591, 178973354, 178970560, 715860463, 715849600, 2863377048, 2863365834

Offset: 0

Author

Marks R. Nester

Keywords

• nonn

Comments

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..500

Crossrefs

Cf. A007581, A124303, A056460, A284826.

Formula

a(n) = Sum_{d|n} mu(d)*A124303(ceiling(n/(2*d))) for n > 0.

a(n) = Sum_{k=1..4} A284826(n, k) for n > 0. - Andrew Howroyd, Oct 02 2019

Extensions

a(0)=1 prepended and terms a(32) and beyond from Andrew Howroyd, Oct 02 2019