A012968 - OEIS

%I #6 Nov 28 2016 20:51:24

%S 0,2,-1,16,-54,876,-6630,122904,-1558536,33455520,-601095600,

%T 14941817856,-346714064928,9916498091808,-280431880000272,

%U 9142107223322304,-303483440198252160,11161636493381966592

%N arctanh(arctan(x)+log(x+1))=2*x-1/2!*x^2+16/3!*x^3-54/4!*x^4+876/5!*x^5...

%t With[{nn=30},CoefficientList[Series[ArcTanh[ArcTan[x]+Log[x+1]],{x,0,nn}],x] Range[0,nn]!] (* _Ray Chandler_, Nov 28 2016 *)

%K sign

%O 0,2

%A Patrick Demichel (patrick.demichel(AT)hp.com)