A012217 arcsinh(arctan(arcsinh(x)))=x-4/3!*x^3+92/5!*x^5-5216/7!*x^7...

1, -4, 92, -5216, 551504, -94170176, 23756009664, -8329952294400, 3882725102061824, -2324928136769545216, 1740643970081187412992, -1594058498088175066406912, 1753510369493317462917828608

Offset

0,2

Links

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

Mathematica

With[{nn=30}, Take[CoefficientList[Series[ArcSinh[ArcTan[ArcSinh[x]]], {x, 0, nn}], x] Range[0, nn-1]!, {2, -1, 2}]] (* Harvey P. Dale, Mar 10 2013 *)

Crossrefs

Sequence in context: A265238 A322769 A012071 * A012135 A221287 A177411

Adjacent sequences: A012214 A012215 A012216 * A012218 A012219 A012220

Keyword

sign

Author

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

Status

approved