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%I #18 Jul 24 2018 03:11:44
%S 1,-1,-11,-253,-9463,-491609,-30257347,-1480493589,177416283793,
%T 125705754161615,53738108098148101,22477151211215445843,
%U 9977406312993326490265,4802660699035958910256759
%N Expansion of e.g.f. cos(sinh(tan(x))), even terms only.
%H G. C. Greubel, <a href="/A009055/b009055.txt">Table of n, a(n) for n = 0..234</a>
%p seq(coeff(series(factorial(n)*cos(sinh(tan(x))), x,n+1),x,n),n=0..30,2); # _Muniru A Asiru_, Jul 24 2018
%t With[{nmax = 60}, CoefficientList[Series[Cos[Sinh[Tan[x]]], {x, 0, nmax}], x]*Range[0, nmax]!][[1 ;; -1 ;; 2]] (* _G. C. Greubel_, Jul 23 2018 *)
%o (PARI) x='x+O('x^60); v=Vec(serlaplace(cos(sinh(tan(x))))); vector(#v\2,n,v[2*n-1]) \\ _G. C. Greubel_, Jul 23 2018
%K sign
%O 0,3
%A _R. H. Hardin_
%E Extended with signs by _Olivier Gérard_, Mar 15 1997