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A292359
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E.g.f.: Product_{k>=1} (1 - x^k/k).
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5
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1, -1, -1, 1, 2, 26, -6, 414, -624, -288, -20880, 164880, -9756000, 43529760, -324404640, -4052492640, -48521410560, 1168445053440, -26858914467840, 341240066334720, -5752671815116800, 49267037136844800, -769468911734476800, 39863275492626432000
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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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E.g.f.: exp(-Sum_{k>=1} Sum_{j>=1} x^(j*k)/(k*j^k)). - Ilya Gutkovskiy, May 27 2018
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MATHEMATICA
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nmax = 20; CoefficientList[Series[Product[(1 - x^k/k), {k, 1, nmax}], {x, 0, nmax}], x] * Range[0, nmax]! (* Vaclav Kotesovec, Sep 15 2017 *)
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PROG
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(PARI) {a(n) = n!*polcoeff(prod(k=1, n, 1-x^k/k+x*O(x^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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