A012683 arcsinh(tanh(x)*arctan(x))=2/2!*x^2-16/4!*x^4+200/6!*x^6+1024/8!*x^8...

2, -16, 200, 1024, -523232, 36263680, 7024697472, -3839533326336, 933770326393344, 5856130402316288, -153024990104004376576, 83925295292036381278208, 4161808298471932199182336

Offset

0,1

Links

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

Mathematica

With[{nn=30}, Take[CoefficientList[Series[ArcSinh[Tanh[x]ArcTan[x]], {x, 0, nn}], x] Range[0, nn]!, {3, -1, 2}]] (* Harvey P. Dale, Jun 10 2024 *)

Crossrefs

Sequence in context: A209586 A334237 A356585 * A012677 A158212 A300456

Adjacent sequences: A012680 A012681 A012682 * A012684 A012685 A012686

Keyword

sign

Author

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

Status

approved