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A330649 E.g.f.: Product_{k>=1} 1 / (1 - x^k/(k!*(1 - x)^k)). 1

%I #82 Feb 16 2020 05:45:01

%S 1,1,5,34,299,3226,41202,607545,10153831,189628750,3913009178,

%T 88406043991,2170372901534,57531498837515,1637713270797411,

%U 49830222530823615,1613950394999111903,55444724259894089718,2013760368429942861810,77105255895256112519259

%N E.g.f.: Product_{k>=1} 1 / (1 - x^k/(k!*(1 - x)^k)).

%F a(n) = Sum_{k=0..n} binomial(n-1,k-1) * A005651(k) * n! / k!.

%F a(n) ~ c * 2^(n-1) * n!, where c = A247551 = 2.52947747207915264818... - _Vaclav Kotesovec_, Feb 16 2020

%t nmax = 19; CoefficientList[Series[Product[1/(1 - x^k/(k! (1 - x)^k)), {k, 1, nmax}], {x, 0, nmax}], x] Range[0, nmax]!

%t Table[Sum[Binomial[n - 1, k - 1] Total[Apply[Multinomial, IntegerPartitions[k], {1}]] n!/k!, {k, 0, n}], {n, 0, 19}]

%o (PARI) seq(n)={Vec(serlaplace(prod(k=1, n, 1 / (1 - x^k/(k!*(1 - x)^k)) + O(x*x^n))))} \\ _Andrew Howroyd_, Feb 13 2020

%Y Cf. A005651, A084358, A218482, A320566, A332024.

%K nonn

%O 0,3

%A _Ilya Gutkovskiy_, Feb 13 2020

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Last modified March 28 12:59 EDT 2024. Contains 371254 sequences. (Running on oeis4.)