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%I #9 Aug 16 2018 08:54:09
%S 2,4,1040,4640,331520,178470400,24593254400,666964480000,
%T 66553013755904000,4091041782710272000,5311565147410595840000,
%U 211592629697932820480000,121215491006931795968000000
%N Numerators of e.g.f.: -cot(arctanh(x)), odd powers only.
%e cot(arctanh(x)) = 1/x - (2/3)*x - (4/3)*x^3/3! - (1040/63)*x^5/5! - ...
%t With[{nn=30},Take[Numerator[CoefficientList[Series[-Cot[ArcTanh[x]],{x,0,nn}],x] Range[0,nn-1]!],{2,-1,2}]]//Quiet (* _Harvey P. Dale_, Jul 08 2017 *)
%Y Denominators are in A102065.
%K nonn,frac
%O 1,1
%A _Ralf Stephan_, Dec 28 2004