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A254081
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Number of primitive (=aperiodic) n-bead necklaces with colored beads of exactly 9 different colors.
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2
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40320, 1632960, 38102400, 673596000, 10035083520, 133102569600, 1623972430080, 18615386790000, 203401119841920, 2140495978400640, 21860934514473600, 217932712305073920, 2130148393318725120, 20485620162998625600, 194378546540211264000, 1823813323809879402000
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OFFSET
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9,1
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LINKS
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MAPLE
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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);
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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