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 A132960 a(n) = n!*Sum_{d|n} (-1)^(d+1)/(d!*(n/d)^d). 8
 1, 0, 3, 2, 25, 94, 721, 3674, 42561, 291248, 3628801, 34254604, 479001601, 5337581534, 88966701825, 1140807642974, 20922789888001, 321094542593824, 6402373705728001, 109338195253235948, 2457732174030848001 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,3 LINKS G. C. Greubel, Table of n, a(n) for n = 1..450 FORMULA E.g.f.: Sum_{k>0}(1-exp(-x^k/k)). MATHEMATICA Rest[ Range[0, 22]! CoefficientList[ Series[ - Sum[ Exp[ -x^k/k], {k, 25}], {x, 0, 22}], x]] (* Robert G. Wilson v, Sep 13 2007 *) PROG (PARI) a(n) = n!*sumdiv(n, d, (-1)^(d+1)/(d!*(n/d)^d)); \\ Michel Marcus, Sep 29 2017 CROSSREFS Cf. A005225, A132958, A132959, A132961, A132962, A132963. Sequence in context: A165714 A090883 A100645 * A009574 A059422 A102056 Adjacent sequences:  A132957 A132958 A132959 * A132961 A132962 A132963 KEYWORD easy,nonn AUTHOR Vladeta Jovovic, Sep 06 2007 EXTENSIONS More terms from Robert G. Wilson v, Sep 13 2007 STATUS approved

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Last modified September 20 10:51 EDT 2021. Contains 347584 sequences. (Running on oeis4.)