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%I #12 Nov 03 2019 16:03:47
%S 0,0,0,1,5,13,43,116,335,920,2591,7173,20125,56260,158333,446098,
%T 1262225,3579227,10181479,29028405,82968695,237634700,682014587,
%U 1960951980,5647919640,16292680600,47069103545,136166476875,394418199725,1143821408316,3320790074371
%N Number of n-bead necklace structures which are not self-equivalent under a nonzero rotation using exactly three different colored beads.
%C Permuting the colors does not change the structure.
%H Andrew Howroyd, <a href="/A328740/b328740.txt">Table of n, a(n) for n = 1..200</a>
%F a(p) = A056296(p) = A056304(p) for prime p >= 5.
%e For n=5, the 5 necklace structures are: aaabc, aabac, aabbc, aabcb, ababc.
%Y Column 3 of A327693.
%Y Cf. A056296, A056304, A328741, A328742.
%K nonn
%O 1,5
%A _Andrew Howroyd_, Oct 26 2019