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A189424
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Expansion of e.g.f exp(log(1+x)+2*log(1+x)^2).
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1
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1, 1, 4, 0, 44, -220, 2056, -19544, 213216, -2571552, 34036224, -489916416, 7614555648, -127028029440, 2262903109632, -42857715985920, 859647858427392, -18200106158320128, 405498290896693248, -9482120962982547456, 232156555727228971008
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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_{m=1..n} (Sum_{k=m..n} (k!*binomial(m,k-m)*2^(k-m)*Stirling1(n,k))/m!), n > 0, a(0) = 1.
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MAPLE
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S:= series(exp(log(1+x)+2*log(1+x)^2), x, 31):
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MATHEMATICA
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With[{nn=20}, CoefficientList[Series[Exp[Log[1+x]+2Log[1+x]^2], {x, 0, nn}], x] Range[0, nn]!] (* Harvey P. Dale, Dec 27 2014 *)
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PROG
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(Maxima)
a(n):=sum(sum(k!*binomial(m, k-m)*2^(k-m)*stirling1(n, k), k, m, n)/m!, m, 1, 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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