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A275428
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Number of set partitions of [n] such that ten is a multiple of each block size.
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2
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1, 1, 2, 4, 10, 27, 82, 274, 988, 3880, 16175, 72205, 340660, 1697060, 8906990, 48911059, 281486144, 1687198848, 10535484376, 68349098640, 459596780618, 3202506672898, 23052054364956, 171418420964352, 1314125642973640, 10375794542251692, 84315714183790792
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OFFSET
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0,3
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LINKS
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FORMULA
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E.g.f.: exp(x+x^2/2+x^5/5!+x^10/10!).
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MAPLE
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a:= proc(n) option remember; `if`(n=0, 1, add(
`if`(j>n, 0, a(n-j)*binomial(n-1, j-1)), j=[1, 2, 5, 10]))
end:
seq(a(n), n=0..30);
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MATHEMATICA
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a[n_] := a[n] = If[n == 0, 1, Sum[If[j > n, 0, a[n-j]*Binomial[n-1, j-1]], {j, {1, 2, 5, 10}}]];
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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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