cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A298374 Expansion of e.g.f. 1/(1 - x)^exp(-x).

Original entry on oeis.org

1, 1, 0, 0, 6, 15, 65, 595, 4004, 32865, 322307, 3316511, 37845214, 471644173, 6319617369, 91114344217, 1404670896264, 23050054222177, 401305630237239, 7387282161642715, 143360257370842146, 2925289119525173741, 62612350725688075941, 1402681525332544374325
Offset: 0

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Author

Ilya Gutkovskiy, Jan 18 2018

Keywords

Comments

Exponential transform of A002741.

Examples

			1/(1 - x)^exp(-x) = 1 + x/1! + 6*x^4/4! + 15*x^5/5! + 65*x^6/6! + 595*x^7/7! + ...
		

Crossrefs

Programs

  • Maple
    a:=series(1/(1-x)^exp(-x),x=0,24): seq(n!*coeff(a,x,n),n=0..23); # Paolo P. Lava, Mar 26 2019
  • Mathematica
    nmax = 23; CoefficientList[Series[1/(1 - x)^Exp[-x], {x, 0, nmax}], x] Range[0, nmax]!
  • PARI
    my(N=30, x='x+O('x^N)); Vec(serlaplace(1/(1-x)^exp(-x))) \\ Seiichi Manyama, May 03 2022

Formula

a(n) ~ n! * n^(exp(-1)-1) / Gamma(exp(-1)). - Vaclav Kotesovec, May 04 2018