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A013544 Numerator of the coefficient [x^(2n+1)] of tanh(cosec(x)-coth(x)). 1
-1, 7, -1013, 64763, -3009173, 5341411709, -857007547621, 28828641126011, -1030088087041163819, 108508429719458111069, -2005462402042629244533103, 41348510060126079043949299, -132583025047910486114666220223 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

LINKS

G. C. Greubel, Table of n, a(n) for n = 0..200

EXAMPLE

-x/6 +7*x^3/162 -1013*x^5/816480 +64763*x^7/88179840 -...

MATHEMATICA

Numerator[Take[CoefficientList[Series[Tanh[Csc[x] - Coth[x]], {x, 0, 26}], x], {2, -1, 2}]] (* G. C. Greubel, Nov 13 2016 *)

CROSSREFS

Sequence in context: A173852 A062841 A110718 * A250914 A004807 A139781

Adjacent sequences:  A013541 A013542 A013543 * A013545 A013546 A013547

KEYWORD

sign,frac

AUTHOR

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

EXTENSIONS

Name edited by R. J. Mathar, Dec 21 2011

STATUS

approved

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Last modified May 28 16:16 EDT 2017. Contains 287241 sequences.