OFFSET
0,2
LINKS
G. C. Greubel, Table of n, a(n) for n = 0..200
EXAMPLE
-x/6 + 7*x^3/162 - 17*x^5/13608 + 913*x^7/1224720 - 93959*x^9/1745960832 + ...
MATHEMATICA
Numerator[Take[CoefficientList[Series[ArcTan[Csc[x] - Coth[x]], {x, 0, 26}], x], {2, -1, 2}]] (* G. C. Greubel, Nov 13 2016 *)
CROSSREFS
KEYWORD
sign,frac
AUTHOR
Patrick Demichel (patrick.demichel(AT)hp.com)
EXTENSIONS
Name edited by R. J. Mathar, Dec 21 2011
STATUS
approved