A012988 Expansion of e.g.f. arctan(arctan(x)+arcsin(x)) (odd powers only).

2, -17, 881, -111919, 26533505, -10100912631, 5639610453681, -4341268802719599, 4406801928941004417, -5703476313460410444519, 9166802819086051420527153, -17912428427903720892882856479

Offset

0,1

Links

Table of n, a(n) for n=0..11.

Example

2*x - 17/3!*x^3 + 881/5!*x^5 - 111919/7!*x^7 ...

Mathematica

With[{nn=30}, Take[CoefficientList[Series[ArcTan[ArcTan[ x]+ ArcSin[x]], {x, 0, nn}], x]Range[0, nn-1]!, {2, -1, 2}]] (* Harvey P. Dale, Sep 30 2011 *)

Crossrefs

Sequence in context: A012944 A013099 A013060 * A261535 A188717 A327020

Adjacent sequences: A012985 A012986 A012987 * A012989 A012990 A012991

Keyword

sign

Author

Patrick Demichel

Extensions

Definition corrected by Harvey P. Dale, Sep 30 2011

Status

approved