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%I #7 Aug 01 2021 16:57:02
%S -1,-1,125,5585,146835,199553825,16151898425,3951808537625,
%T 54159749674008875,7187045526725631125,4971794789793419144375,
%U 836133262846273312334375,125448452657856727433328125
%N Numerators of e.g.f. cosec(arctanh(x)).
%e cosec(arctanh(x)) = 1/x - x/6 - 1/12*x^3/3! + 125/126x^5/5! +...
%e cosech(arctan(x)) = 1/x + x/6 - 1/12*x^3/3! - 125/126x^5/5! +...
%t With[{nn=30},Take[Numerator[CoefficientList[Series[Csc[ArcTanh[x]],{x,0,nn}],x] Range[0,nn-1]!],{2,-1,2}]]//Quiet (* _Harvey P. Dale_, Aug 01 2021 *)
%Y Denominators are in A102077.
%K sign,frac
%O 1,3
%A _Ralf Stephan_, Dec 31 2004