login

Reminder: The OEIS is hiring a new managing editor, and the application deadline is January 26.

arctanh(arctan(arcsinh(x)))=x-1/3!*x^3+17/5!*x^5-617/7!*x^7+44417/9!*x^9...
0

%I #6 Nov 28 2016 17:57:52

%S 1,-1,17,-617,44417,-5210129,909126033,-220910314809,71341157623169,

%T -29556627270426145,15282372258542389905,-9645984260739983339273,

%U 7298836347461102485422593,-6521512480584315170326457393

%N arctanh(arctan(arcsinh(x)))=x-1/3!*x^3+17/5!*x^5-617/7!*x^7+44417/9!*x^9...

%t With[{nn=30},Take[CoefficientList[Series[ArcTanh[ArcTan[ArcSinh[x]]],{x,0,nn}],x] Range[0,nn-1]!,{2,-1,2}]] (* _Ray Chandler_, Nov 28 2016 *)

%K sign

%O 0,3

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