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%I #12 Nov 29 2016 10:46:50
%S 0,1,6,90,2520,120960,9979200,1377295920,285145660800,78922558915200,
%T 27250976424672000,11359413770434329600,5628391828843104921600,
%U 3284252230408078849920000,2238997166752030045320960000
%N -arctan(log(x+1)-arctanh(x))=1/2!*x^2+6/4!*x^4+90/6!*x^6+2520/8!*x^8...
%t With[{nn=30},Take[CoefficientList[Series[-ArcTan[Log[x+1]-ArcTanh[x]],{x,0,nn}],x] Range[0,nn]!,{1,-1,2}]] (* _Ray Chandler_, Nov 29 2016 *)
%K nonn
%O 0,3
%A Patrick Demichel (patrick.demichel(AT)hp.com)