login
A056349
Number of primitive (period n) bracelets using exactly three different colored beads.
1
0, 0, 1, 6, 18, 55, 147, 405, 1083, 2961, 8043, 22182, 61278, 170883, 477910, 1344825, 3795750, 10757763, 30572427, 87146139, 248991674, 713088309, 2046303339, 5883410760, 16944543792, 48879708297
OFFSET
1,4
COMMENTS
Turning over will not create a new bracelet.
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]
FORMULA
sum mu(d)*A056343(n/d) where d|n.
CROSSREFS
Cf. A056288.
Sequence in context: A099856 A292295 A183913 * A278768 A035070 A075386
KEYWORD
nonn
STATUS
approved