A009254 Expansion of exp(tan(x)/cosh(x)).

1, 1, 1, 0, -3, 12, 117, 336, -903, -2096, 111529, 1043328, 687093, -29488704, 320199453, 8894706432, 44530596081, -389860902656, 254346923089, 170568226222080, 2006766293627373, -6327905330549760, -141849542553657147

Offset: 0

Author

R. H. Hardin

Keywords

• sign
• easy

Programs

Mathematica

With[{nn=30},CoefficientList[Series[Exp[Tan[x]/Cosh[x]],{x,0,nn}],x] Range[0,nn]!] (* Harvey P. Dale, Mar 07 2018 *)

Extensions

Extended with signs by Olivier Gérard, Mar 15 1997

Previous Mathematica program replaced by Harvey P. Dale, Mar 07 2018