A009768 Expansion of e.g.f. tanh(exp(x)*x).

0, 1, 2, 1, -20, -159, -594, 2465, 69560, 665665, 1593850, -67177791, -1413216540, -12990964063, 64480265318, 4811655319393, 90259507840240, 540272971703937, -20890652777843598, -798235260367432831, -12766815370452348580

Offset: 0

Author

R. H. Hardin

Keywords

• sign
• easy

Links

• Seiichi Manyama, Table of n, a(n) for n = 0..100

Crossrefs

Cf. A009121, A009565, A009635, A216401.

Programs

Mathematica

With[{nn=20},CoefficientList[Series[Tanh[Exp[x]*x],{x,0,nn}],x] Range[0,nn]!] (* Harvey P. Dale, Jun 03 2023 *)

PARI

my(x='x+O('x^30)); concat(0, Vec(serlaplace(tanh(exp(x)*x)))) \\ Michel Marcus, Oct 01 2021

Extensions

Extended with signs by Olivier Gérard, Mar 15 1997

Previous Mathematica program replaced by Harvey P. Dale, Jun 03 2023