A254081 Number of primitive (=aperiodic) n-bead necklaces with colored beads of exactly 9 different colors.

40320, 1632960, 38102400, 673596000, 10035083520, 133102569600, 1623972430080, 18615386790000, 203401119841920, 2140495978400640, 21860934514473600, 217932712305073920, 2130148393318725120, 20485620162998625600, 194378546540211264000, 1823813323809879402000

Offset: 9

Author

Alois P. Heinz, Jan 25 2015

Keywords

• nonn

Links

• Alois P. Heinz, Table of n, a(n) for n = 9..1000

Crossrefs

Column k=9 of A254040.

Programs

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);