login

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).

A254080
Number of primitive (=aperiodic) n-bead necklaces with colored beads of exactly 8 different colors.
2
5040, 161280, 3024000, 43545600, 534330720, 5891719680, 60227481600, 582295633920, 5397245411040, 48421936442880, 423440785541760, 3628271603174400, 30584600246448864, 254421149466401280, 2093705950217414400, 17078070713147136000, 138294714025711281360
OFFSET
8,1
LINKS
MAPLE
with(numtheory):
b:= proc(n, k) option remember; `if`(n=0, 1,
add(mobius(n/d)*k^d, d=divisors(n))/n)
end:
a:= n-> add(b(n, 8-j)*binomial(8, j)*(-1)^j, j=0..8):
seq(a(n), n=8..30);
CROSSREFS
Column k=8 of A254040.
Sequence in context: A191685 A213877 A135456 * A228910 A258419 A355023
KEYWORD
nonn
AUTHOR
Alois P. Heinz, Jan 25 2015
STATUS
approved