A012204 arcsin(arctan(arctan(x)))=x-3/3!*x^3+57/5!*x^5-2755/7!*x^7+251601/9!*x^9...

1, -3, 57, -2755, 251601, -37281923, 8163849353, -2479580033411, 997801392400929, -513852593272870403, 329599574990913085529, -257652341842242812773955, 241116753509976748759134193

Offset

0,2

Links

Table of n, a(n) for n=0..12.

Mathematica

With[{nn=30}, Take[CoefficientList[Series[ArcSin[ArcTan[ArcTan[x]]], {x, 0, nn}], x] Range[0, nn-1]!, {2, -1, 2}]] (* Ray Chandler, Nov 28 2016 *)

Crossrefs

Sequence in context: A210674 A281184 A012064 * A000281 A350306 A377651

Adjacent sequences: A012201 A012202 A012203 * A012205 A012206 A012207

Keyword

sign

Author

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

Status

approved