|
| |
|
|
A012981
|
|
arctanh(arctan(x)+sin(x))=2*x+13/3!*x^3+553/5!*x^5+57839/7!*x^7...
|
|
0
|
|
|
|
2, 13, 553, 57839, 11359153, 3579398359, 1655031037177, 1054978773554159, 886822655405158113, 950463966040325692455, 1265021553451798971633001, 2047001827823001219625900543, 3957634961967849174268972586001
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
|
OFFSET
|
0,1
|
|
|
LINKS
|
|
|
|
FORMULA
|
a(n) ~ (2*n)! / r^(2*n+1), where r = 0.5343315247229429263511748056113294391694... is the root of the equation arctan(r)+sin(r) = 1. - Vaclav Kotesovec, Feb 05 2015
|
|
|
MATHEMATICA
|
nn = 20; Table[(CoefficientList[Series[ArcTanh[ArcTan[x] + Sin[x]], {x, 0, 2*nn+1}], x] * Range[0, 2*nn+1]!)[[n]], {n, 2, 2*nn, 2}] (* Vaclav Kotesovec, Feb 05 2015 *)
|
|
|
CROSSREFS
|
|
|
|
KEYWORD
|
nonn
|
|
|
AUTHOR
|
Patrick Demichel (patrick.demichel(AT)hp.com)
|
|
|
STATUS
|
approved
|
| |
|
|
