A328742 Number of n-bead necklace structures which are not self-equivalent under a nonzero rotation using a maximum of three different colored beads.

1, 1, 0, 1, 2, 8, 17, 52, 130, 363, 968, 2684, 7338, 20440, 56836, 159424, 448130, 1266080, 3586479, 10195276, 29054568, 83018624, 237729932, 682196948, 1961301330, 5648590728, 16293970840, 47071589049, 136171269780, 394427456120, 1143839302904, 3320824711204

Offset: 0

Author

Andrew Howroyd, Oct 26 2019

Keywords

• nonn

Comments

Permuting the colors does not change the structure.

Links

• Andrew Howroyd, Table of n, a(n) for n = 0..200

Crossrefs

Cf. A002075, A002076, A327693, A328740.

Formula

a(n) = Sum_{k=1..3} A327693(n, k) for n > 0.

a(p) = A002075(p) for prime p >= 5.