A012462 Arcsinh(arctan(x)^2) = 2/2!*x^2 - 16/4!*x^4 + 248/6!*x^6 - 3456/8!*x^8 + ...

0, 2, -16, 248, -3456, -164448, 17537280, 5001348480, -3047690956800, 999150768960000, -194340969261158400, -28292890791044597760, 48811395838790000148480, -15658656394130132870062080, -19215487887156327014813859840, 37972554002174500707798919249920

Offset: 0

Author

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

Keywords

• sign

Programs

Mathematica

With[{nn=30},Take[CoefficientList[Series[ArcSinh[ArcTan[x]^2],{x,0,nn}],x] Range[0,nn]!,{1,-1,2}]] (* Harvey P. Dale, May 06 2013 *)

Extensions

Definition clarified by Harvey P. Dale, May 06 2013