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%I #16 Apr 12 2017 23:19:39
%S 2,8,248,11328,849312,94857600,14819214720,3091936512000,
%T 831657655349760,280473756197529600,115967597965430077440,
%U 57712257892456911912960,34039765801079493369569280
%N Coefficients in the expansion sinh(arcsin(x)*arcsin(x)) = 2*x^2/2!+8*x^4/4!+248*x^6/6!+11328*x^8/8!+...
%H G. C. Greubel, <a href="/A012345/b012345.txt">Table of n, a(n) for n = 0..223</a>
%F a(n) ~ sqrt(Pi) * cosh(Pi^2/4) * (2*n)! / (2 * n^(3/2)). - _Vaclav Kotesovec_, Feb 08 2015
%e sinh(arcsin(x)*arcsin(x)) = 2*x^2/2! + 8*x^4/4! + 248*x^6/6! + 11328*x^8/8! + ...
%t nn = 20; Table[(CoefficientList[Series[Sinh[ArcSin[x]^2], {x, 0, 2*nn}], x] * Range[0, 2*nn]!)[[n]], {n, 1, 2*nn+1, 2}] (* _Vaclav Kotesovec_, Feb 08 2015 *)
%o (PARI) x='x+O('x^50); v=Vec(serlaplace(sinh(asin(x)*asin(x)))); vector(#v\2,n,v[2*n-1]) \\ _G. C. Greubel_, Apr 11 2017
%K nonn
%O 0,1
%A Patrick Demichel (patrick.demichel(AT)hp.com)