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%I #18 Jul 24 2018 21:22:49
%S 1,-3,-35,-679,-18567,-587499,-9780459,2502478065,742659420913,
%T 178572619407021,44455465546363725,12065488445289701385,
%U 3615507259471920747625,1195750896202918862106309,433676146678880946251117189,170620060022539628512713371809
%N Expansion of e.g.f. cos(tan(x))*x, odd terms only.
%H G. C. Greubel, <a href="/A009071/b009071.txt">Table of n, a(n) for n = 0..240</a>
%F a(n) = (2*n+1)! * [x^(2*n+1)] cos(tan(x))*x. - _Alois P. Heinz_, Oct 01 2012
%t With[{nn=40},Take[CoefficientList[Series[Cos[Tan[x]]*x,{x,0,nn}],x] Range[0,nn-1]!, {2,-1,2}]] (* _Harvey P. Dale_, Oct 01 2012 *)
%o (PARI) x='x+O('x^50); v=Vec(serlaplace(x*cos(tan(x)))); vector((#v-1)\2 ,n,v[2*n-1]) \\ _G. C. Greubel_, Jul 24 2018
%K sign
%O 0,2
%A _R. H. Hardin_
%E Extended with signs by _Olivier Gérard_, Mar 15 1997
%E More terms from _Harvey P. Dale_, Oct 01 2012
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