%I #4 Jan 15 2018 21:06:33
%S 1,-1,12,-327,15883,-1202524,130394253,-19113418989,3632485387276,
%T -867280709024131,253803272212372575,-89250842789856565620,
%U 37105568909251258810585,-17991614679286735149423193,10057557723279565571532112044,-6417980557539322347015938082111
%N Expansion of e.g.f. exp(cos(tanh(x))-1) (even powers only).
%F a(n) = (2*n)! * [x^(2*n)] exp(cos(tanh(x))-1).
%e exp(cos(tanh(x))-1) = 1 - x^2/2! + 12*x^4/4! - 327*x^6/6! + 15883*x^8/8! - 1202524*x^10/10! + ...
%t nmax = 15; Table[(CoefficientList[Series[Exp[Cos[Tanh[x]] - 1], {x, 0, 2 nmax}], x] Range[0, 2 nmax]!)[[n]], {n, 1, 2 nmax + 1, 2}]
%Y Cf. A003711, A009090, A009201, A009202, A009203, A009204, A009238, A009239, A009240, A009241, A009254, A297214, A297215.
%K sign
%O 0,3
%A _Ilya Gutkovskiy_, Jan 15 2018
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