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A013545
Numerator of the coefficient [x^(2n+1)] of the Taylor series arctanh(cosec(x) - coth(x)).
1
-1, 13, 29, 397, 74927, 2570951, 495301, 2978520989, 879781928617, 1962442468445621, 4485273725677799419, 17810142018975186977
OFFSET
0,2
LINKS
G. C. Greubel, Table of n, a(n) for n = 0..200 [Vincenzo Librandi computed the first 100 terms; Terms 101 to 200 computed by G. C. Greubel, Nov 13 2016]
EXAMPLE
-x/6 + 13*x^3/324 + 29*x^5/27216 + 397*x^7/2449440 + 74927*x^9/3491921664 + ... .
MATHEMATICA
Numerator[Take[CoefficientList[Series[ArcTanh[Csc[x] - Coth[x]], {x, 0, 35}], x], {2, -2, 2}]] (* Vincenzo Librandi, Nov 12 2016 *)
CROSSREFS
Sequence in context: A358744 A317897 A195878 * A120273 A104817 A048450
KEYWORD
sign,frac
AUTHOR
Patrick Demichel (patrick.demichel(AT)hp.com)
EXTENSIONS
Name edited by R. J. Mathar, Dec 21 2011
STATUS
approved