A056367 Number of primitive (period n) bracelet structures using exactly three different colored beads.

0, 0, 1, 2, 5, 13, 31, 80, 201, 533, 1401, 3822, 10395, 28859, 80201, 225286, 634265, 1796433, 5100325, 14534758, 41513402, 118879249, 341094843, 980661980, 2824223490, 8146897815, 23535345170

Offset

1,4

Comments

Turning over will not create a new bracelet. Permuting the colors of the beads will not change the structure.

References

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]

Links

Table of n, a(n) for n=1..27.

Formula

A056362(n)-A000046(n).

Crossrefs

Column 3 of A276543.

Cf. A056304.

Sequence in context: A307569 A200772 A099515 * A082733 A095134 A086758

Adjacent sequences: A056364 A056365 A056366 * A056368 A056369 A056370

Keyword

nonn

Author

Marks R. Nester

Status

approved