login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A012727 exp(arctanh(x)*arctan(x))=1+2/2!*x^2+12/4!*x^4+328/6!*x^6+13328/8!*x^8... 1

%I

%S 1,2,12,328,13328,1160352,123701952,22207125120,4532782825728,

%T 1380071532433920,459909185638812672,212375023941305272320,

%U 104929881035116227072000,68350141067274779587092480

%N exp(arctanh(x)*arctan(x))=1+2/2!*x^2+12/4!*x^4+328/6!*x^6+13328/8!*x^8...

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

%K nonn

%O 0,2

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

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified January 27 14:39 EST 2020. Contains 331295 sequences. (Running on oeis4.)