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%I #10 Oct 26 2019 14:30:26
%S 1,1,1,2,5,10,29,72,230,700,2421,8308,30070,108990,403188,1497057,
%T 5607200,21076570,79595257,301492044,1145558141,4363503609,
%U 16660196142,63741248200,244339616370,938255682540,3608668279965,13900021843855,53614339995060,207062143625710
%N Number of primitive (period n) bracelet structures using a maximum of four different colored beads.
%C Turning over will not create a new bracelet. Permuting the colors of the beads will not change the structure.
%D 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]
%H Andrew Howroyd, <a href="/A056363/b056363.txt">Table of n, a(n) for n = 0..200</a>
%F a(n) = Sum_{d|n} mu(d)*A056354(n/d) for n > 0.
%F a(n) = Sum_{k=1..4} A276543(n, k) for n > 0. - _Andrew Howroyd_, Oct 26 2019
%Y Cf. A056300, A056354, A056368, A276543.
%K nonn
%O 0,4
%A _Marks R. Nester_
%E a(0)=1 prepended and terms a(26) and beyond from _Andrew Howroyd_, Oct 26 2019