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A270240
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Number of partitions of n unlabeled objects of 7 colors.
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2
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1, 7, 56, 364, 2198, 12292, 65240, 330262, 1608866, 7575967, 34636896, 154235319, 670752411, 2855122319, 11917598512, 48858820584, 197008297955, 782223365518, 3061514606822, 11822306812232, 45080137355687, 169865159676365, 632916329409504, 2333298558227399
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OFFSET
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0,2
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LINKS
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FORMULA
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G.f.: Product_{j>=1} 1/(1-x^j)^C(j+6,6).
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MAPLE
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with(numtheory):
a:= proc(n) option remember; `if`(n=0, 1, add(add(
d*binomial(d+6, 6), d=divisors(j))*a(n-j), j=1..n)/n)
end:
seq(a(n), n=0..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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