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%I #26 Jan 22 2018 03:04:18
%S 1,2,36,944,45136,3263072,334656960,46199442176,8260388524288,
%T 1857027989588480,512693973356712960,170529221696594702336,
%U 67257392621575577522176,31036094843772953163063296
%N Expansion of e.g.f. sin(x)/cos(sinh(x)) (odd powers only).
%H G. C. Greubel, <a href="/A009554/b009554.txt">Table of n, a(n) for n = 1..233</a>
%F a(n) ~ (2*n-1)! * 4 * sin(arcsinh(Pi/2)) / (sqrt(4+Pi^2) * (arcsinh(Pi/2))^(2*n)). - _Vaclav Kotesovec_, Jan 23 2015
%t With[{nn=30},Take[CoefficientList[Series[Sin[x]/Cos[Sinh[x]],{x,0,nn}], x]Range[0,nn-1]!,{2,-1,2}]] (* _Harvey P. Dale_, Jan 19 2012 *)
%o (PARI) x='x+O('x^50); v=Vec(serlaplace(sin(x)/cos(sinh(x)))); vector((#v-1)\2 ,n,v[2*n-1]) // _G. C. Greubel_, Jan 20 2018
%K nonn
%O 1,2
%A _R. H. Hardin_
%E Extended and signs tested by _Olivier Gérard_, Mar 15 1997
%E Offset corrected by _Vaclav Kotesovec_, Jan 23 2015
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