A009176 - OEIS

A009176

Expansion of e.g.f.: cosh(x)*cos(tan(x)).

1, 0, -12, -216, -5296, -168128, -5391680, 38412672, 61881368832, 16576603568128, 4120672559178752, 1085659391947229184, 313198080458495610880, 99633528964523733598208, 34860299883730859703910400

(list; graph; refs; listen; history; text; internal format)

OFFSET

0,3

LINKS

Table of n, a(n) for n=0..14.

MATHEMATICA

With[{nn=30}, Take[CoefficientList[Series[Cosh[x]*Cos[Tan[x]], {x, 0, nn}], x] Range[ 0, nn]!, {1, -1, 2}]] (* Harvey P. Dale, May 11 2020 *)

CROSSREFS

Sequence in context: A034788 A082165 A006689 * A374892 A087585 A297503

Adjacent sequences: A009173 A009174 A009175 * A009177 A009178 A009179

KEYWORD

sign

AUTHOR

R. H. Hardin

EXTENSIONS

Extended with signs by Olivier Gérard, Mar 15 1997

Previous Mathematica program replaced by Harvey P. Dale, May 11 2020

STATUS

approved