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A191353
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E.g.f. (1+x)^(x+x^2)
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0
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1, 0, 2, 3, 8, 70, 54, 1428, 2624, 27144, 158040, 653400, 6245832, 48636432, -32399472, 6915245400, -59561508480, 1236398222400, -16660175380416, 304602764156928, -5255061417083520
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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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a(n)=(sum(k=1..n, sum(i=k..n, (binomial(k,i-k)*stirling1(n-i,k))/(n-i)!)))*n!, n>0, a(0)=1.
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PROG
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(Maxima)
a2(n):=(sum(sum((binomial(k, i-k)*stirling1(n-i, k))/(n-i)!, i, k, n), k, 1, n))*n!;
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CROSSREFS
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KEYWORD
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sign
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AUTHOR
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STATUS
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approved
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