A009208 Expansion of exp(sin(x))/cosh(x).

1, 1, 0, -3, -4, 17, 56, -203, -1072, 5473, 34368, -254067, -1781440, 16540721, 132000896, -1419027899, -12912385792, 156472224961, 1604411553792, -21673957780323, -247155791205376, 3688273509233489, 46275148760619008

Offset

0,4

Links

Table of n, a(n) for n=0..22.

Formula

a(n) ~ n! * cos(Pi*n/2 - sinh(Pi/2)) * 2^(n+2) / Pi^(n+1). - Vaclav Kotesovec, Jul 02 2015

Mathematica

CoefficientList[Series[Exp[Sin[x]]/Cosh[x], {x, 0, 20}], x] * Range[0, 20]! (* Vaclav Kotesovec, Jul 02 2015 *)

Crossrefs

Sequence in context: A296277 A303480 A254200 * A296283 A051473 A039563

Adjacent sequences: A009205 A009206 A009207 * A009209 A009210 A009211

Keyword

sign,easy

Author

R. H. Hardin

Extensions

Extended with signs by Olivier Gérard, Mar 15 1997

Status

approved