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A013542 Numerator of the coefficient [x^(2n+1)] of the Taylor series sinh(cosec(x) - coth(x)). 1
-1, 53, 3341, 391337, 710371933, 6178130243, 225570264096917, 1546226961439379, 5665951032145572087083, -1602619428542796266047, 218332153959703843484481031721, -149315097238822774731841867 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

COMMENTS

A bisection of A013536. Denominators appear to be a bisection of A202382.

LINKS

G. C. Greubel, Table of n, a(n) for n = 0..193

EXAMPLE

-x/6 + 53*x^3/1296 + 3341*x^5/6531840 + 391337*x^7/1410877440 + ...

MATHEMATICA

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

CROSSREFS

Sequence in context: A243231 A280357 A300406 * A200917 A234630 A088784

Adjacent sequences:  A013539 A013540 A013541 * A013543 A013544 A013545

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 December 3 05:05 EST 2021. Contains 349445 sequences. (Running on oeis4.)