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A254081
Number of primitive (=aperiodic) n-bead necklaces with colored beads of exactly 9 different colors.
2
40320, 1632960, 38102400, 673596000, 10035083520, 133102569600, 1623972430080, 18615386790000, 203401119841920, 2140495978400640, 21860934514473600, 217932712305073920, 2130148393318725120, 20485620162998625600, 194378546540211264000, 1823813323809879402000
OFFSET
9,1
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, 9-j)*binomial(9, j)*(-1)^j, j=0..9):
seq(a(n), n=9..30);
CROSSREFS
Column k=9 of A254040.
Sequence in context: A029576 A179966 A133068 * A228911 A213878 A179063
KEYWORD
nonn
AUTHOR
Alois P. Heinz, Jan 25 2015
STATUS
approved