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A009321
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E.g.f. log(1 + log(1+x)*exp(x)).
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2
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0, 1, 0, 1, -5, 23, -129, 894, -7202, 65365, -661763, 7412348, -91009060, 1214988851, -17522921545, 271538506004, -4499710415184, 79404970485241, -1486680068450391, 29435486083635796, -614519419914446388
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OFFSET
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0,5
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LINKS
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FORMULA
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a(n)=sum(k=1..n, ((-1)^(k-1)*(k-1)!*sum(i=0..n-k, binomial(n,i)*(k^i*stirling1(n-i,k))))). - Vladimir Kruchinin, Jun 14 2011
a(n) ~ (n-1)! * (-1)^(n+1) / (1-exp(-r))^n, where r = 2.5051123308583601790988703653235907822189... is the root of the equation exp(-1 + exp(-r))*r = 1. - Vaclav Kotesovec, Jan 24 2015
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MATHEMATICA
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CoefficientList[Series[Log[1 + E^x*Log[1 + x]], {x, 0, 20}], x] * Range[0, 20]! (* Vaclav Kotesovec, Jan 24 2015 *)
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PROG
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(Maxima)
a(n):=sum(((-1)^(k-1)*(k-1)!*sum(binomial(n, i)*(k^i*stirling1(n-i, k)), i, 0, n-k)), k, 1, n); /* Vladimir Kruchinin, Jun 14 2011 */
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CROSSREFS
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KEYWORD
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sign,easy
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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