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%I #14 Oct 24 2019 23:02:25
%S 0,0,0,1,2,11,33,137,478,1851,6845,26148,98406,374010,1416251,5380907,
%T 20440250,77795428,296384565,1131011633,4321964768,16541275068,
%U 63400061153,243358803904,935431121462,3600520831215,13876485252323,53546253055179,206864927506166,800068244639812
%N Number of bracelet structures using exactly 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="/A056359/b056359.txt">Table of n, a(n) for n = 1..200</a>
%F a(n) = A056354(n) - A056353(n).
%Y Column 4 of A152176.
%Y Cf. A056297, A056353, A056354, A214309.
%K nonn
%O 1,5
%A _Marks R. Nester_
%E Terms a(27) and beyond from _Andrew Howroyd_, Oct 24 2019