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Expansion of e.g.f. sinh(tan(x))/cos(x), odd powers only.
1

%I #14 Jan 31 2018 03:18:14

%S 1,6,92,2688,127312,8850336,845380928,105911556096,16814357324032,

%T 3294279618252288,779927283014454272,219346023009485242368,

%U 72245888404549697916928,27535159087648660044718080,12019428370649765064698642432,5955630440267924458161515003904

%N Expansion of e.g.f. sinh(tan(x))/cos(x), odd powers only.

%H G. C. Greubel, <a href="/A009607/b009607.txt">Table of n, a(n) for n = 0..239</a>

%t With[{nn = 50}, CoefficientList[Series[Sinh[Tan[x]]/Cos[x], {x, 0, nn}], x]*Range[0, nn - 1]!][[2 ;; ;; 2]] (* _G. C. Greubel_, Jan 30 2018 *)

%o (PARI) x='x+O('x^40); v=Vec(serlaplace(sinh(tan(x))/cos(x))); vector((#v-1)\2 ,n,v[2*n-1]) \\ _G. C. Greubel_, Jan 30 2018

%K nonn

%O 0,2

%A _R. H. Hardin_

%E Extended and signs tested by _Olivier GĂ©rard_, Mar 15 1997