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 A298245 Expansion of e.g.f. exp(cos(tanh(x))-1) (even powers only). 0
 1, -1, 12, -327, 15883, -1202524, 130394253, -19113418989, 3632485387276, -867280709024131, 253803272212372575, -89250842789856565620, 37105568909251258810585, -17991614679286735149423193, 10057557723279565571532112044, -6417980557539322347015938082111 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,3 LINKS FORMULA a(n) = (2*n)! * [x^(2*n)] exp(cos(tanh(x))-1). EXAMPLE 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! + ... MATHEMATICA 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}] CROSSREFS Cf. A003711, A009090, A009201, A009202, A009203, A009204, A009238, A009239, A009240, A009241, A009254, A297214, A297215. Sequence in context: A080141 A153468 A230817 * A110101 A185247 A009530 Adjacent sequences:  A298242 A298243 A298244 * A298246 A298247 A298248 KEYWORD sign AUTHOR Ilya Gutkovskiy, Jan 15 2018 STATUS approved

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Last modified December 11 07:44 EST 2019. Contains 329914 sequences. (Running on oeis4.)