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A276928
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Number of ordered set partitions of [n] with at most eight elements per block.
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5
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1, 1, 3, 13, 75, 541, 4683, 47293, 545835, 7087260, 102247542, 1622632110, 28091557362, 526858114926, 10641337416138, 230283052622766, 5315651069181882, 130370668142722722, 3385531828379161890, 92801502294634265418, 2677685131818279016434
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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.: 1/(1-Sum_{i=1..8} x^i/i!).
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MAPLE
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a:= proc(n) option remember; `if`(n=0, 1, add(
a(n-i)*binomial(n, i), i=1..min(n, 8)))
end:
seq(a(n), n=0..25);
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MATHEMATICA
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max = 25; CoefficientList[1/(1-Sum[x^i/i!, {i, 1, 8}]) + O[x]^(max+1), x]* Range[0, max]! (* Jean-François Alcover, May 24 2018 *)
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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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