OFFSET
0,4
COMMENTS
Essentially a bisection of A013529.
LINKS
G. C. Greubel, Table of n, a(n) for n = 0..200
EXAMPLE
1 - x^2/18 + x^4/1944 - 5029*x^6/3674160 + 6697*x^8/264539520 - ...
MATHEMATICA
Numerator[Take[CoefficientList[Series[Cos[Csc[x] - Csch[x]], {x, 0, 25}], x], {1, -1, 2}]] (* G. C. Greubel, Nov 12 2016 *)
CROSSREFS
KEYWORD
sign,frac
AUTHOR
Patrick Demichel (patrick.demichel(AT)hp.com)
EXTENSIONS
Name edited by R. J. Mathar, Dec 20 2011
STATUS
approved