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%I #23 May 02 2024 14:42:50
%S 0,2,-16,288,-9920,541184,-42274816,4449451776,-605255720960,
%T 103187353223168,-21528004660707328,5391886872902762496,
%U -1595781555670951657472,550728986895462989103104
%N Expansion of e.g.f. sin(x)*sin(tanh(x)) (even powers only).
%H G. C. Greubel, <a href="/A009549/b009549.txt">Table of n, a(n) for n = 0..239</a>
%t With[{nmax = 50}, CoefficientList[Series[Sin[x]*Sin[Tanh[x]],{x,0,nmax}], x]*Range[0, nmax]!][[1 ;; ;; 2]] (* _G. C. Greubel_, Jan 20 2018 *)
%o (PARI) x='x+O('x^50); v=Vec(serlaplace(sin(x)*sin(tanh(x)))); concat([0], vector(#v\2,n,v[2*n-1])) \\ _G. C. Greubel_, Jan 20 2018
%K sign
%O 0,2
%A _R. H. Hardin_
%E Extended with signs by _Olivier Gérard_, Mar 15 1997