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%I #20 Feb 15 2018 15:38:13
%S 1,5,41,517,12145,582405,42317081,3759817029,398983432289,
%T 52888501801733,8949712747169929,1870731232726437509,
%U 461089997723562652881,130976488217164121240069,42778996119131902973150329,16067412656453434757397261253,6888568425518076742074506305217
%N Expansion of e.g.f. tan(x)/cos(sin(x)), odd powers only.
%H G. C. Greubel, <a href="/A009755/b009755.txt">Table of n, a(n) for n = 0..240</a>
%p a:= n-> (t-> t!*coeff(series(tan(x)/cos(sin(x)), x, t+1), x, t))(2*n+1):
%p seq(a(n), n=0..17); # _Alois P. Heinz_, Feb 15 2018
%t With[{nn=30},Take[CoefficientList[Series[Tan[x]/Cos[Sin[x]],{x,0,nn}],x] Range[0,nn-1]!,{2,-1,2}]] (* _Harvey P. Dale_, Mar 20 2015 *)
%o (PARI) x='x+O('x^50); v=Vec(serlaplace(tan(x)/cos(sin(x)))); vector((#v-1)\2 ,n,v[2*n-1]) \\ _G. C. Greubel_, Feb 12 2018
%K nonn
%O 0,2
%A _R. H. Hardin_
%E Extended and signs tested by _Olivier Gérard_, Mar 15 1997
%E One additional term from and prior Mathematica program replaced by _Harvey P. Dale_, Mar 20 2015