%I #6 Apr 05 2016 11:59:52
%S 2,-19,1033,-139921,35331409,-14334032601,8528641989385,
%T -6996533376858481,7568756053179558689,-10439411395932267346985,
%U 17880910414730276822733721,-37235878792206753318991025025
%N arctan(arctan(x)+sin(x))=2*x-19/3!*x^3+1033/5!*x^5-139921/7!*x^7...
%t With[{nn=30},Take[CoefficientList[Series[ArcTan[ArcTan[x]+Sin[x]],{x,0,nn}],x] Range[0,nn-1]!,{2,-1,2}]] (* _Harvey P. Dale_, Apr 05 2016 *)
%K sign
%O 0,1
%A Patrick Demichel (patrick.demichel(AT)hp.com)
%E Definition clarified by _Harvey P. Dale_, Apr 05 2016