A009604 - OEIS

%I #19 May 02 2024 14:41:07

%S 1,0,12,280,11536,703296,59653440,6715007104,967972497664,

%T 173764741920768,37986612815698944,9929613975171315712,

%U 3056815269626584895488,1094148286150918628229120

%N Expansion of e.g.f. sinh(tan(x))*cos(x), odd powers only.

%H G. C. Greubel, <a href="/A009604/b009604.txt">Table of n, a(n) for n = 0..239</a>

%t With[{nn = 50}, CoefficientList[Series[Sinh[Tan[x]]*Cos[x], {x, 0, nn}], x] Range[0, nn - 1]!][[2 ;; ;; 2]] (* _G. C. Greubel_, Jan 30 2018 *)

%o (PARI) x='x+O('x^50); v=Vec(serlaplace(sinh(tan(x))*cos(x))); vector((#v-1)\2 ,n,v[2*n-1]) \\ _G. C. Greubel_, Jan 30 2018

%K nonn

%O 0,3

%A _R. H. Hardin_

%E Extended and signs tested by _Olivier Gérard_, Mar 15 1997