A330632 Number of n-bead bracelets using exactly three colors with no adjacent beads having the same color.

0, 0, 1, 3, 3, 10, 9, 27, 29, 75, 93, 221, 315, 684, 1095, 2247, 3855, 7682, 13797, 27009, 49939, 96906, 182361, 352695, 671091, 1296855, 2485533, 4806075, 9256395, 17920857, 34636833, 67159047, 130150587, 252745365, 490853415, 954637555, 1857283155

Offset: 1

Author

Andrew Howroyd, Dec 21 2019

Keywords

• nonn

Links

• Andrew Howroyd, Table of n, a(n) for n = 1..500

Crossrefs

Column 3 of A330341.

Cf. A208539.