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

0,5

Comments

Permuting the colors does not change the structure.

Links

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

Formula

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

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

Crossrefs

Cf. A002075, A002076, A327693, A328740.

Sequence in context: A281470 A295147 A215933 * A341506 A154349 A268068

Adjacent sequences: A328739 A328740 A328741 * A328743 A328744 A328745

Keyword

nonn

Author

Andrew Howroyd, Oct 26 2019

Status

approved