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A013537 Numerator of [x^(2n+1)] of the Taylor expansion sin(cosec(x)-coth(x)). 2
-1, 55, -4219, 802171, -109684277, 760100160121, -265779449377027, 417652078505070229, -7396136516120375032117, 1432995839205684739321951, -63523043223346003438419401363, 2351819493900615585072181702093 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

COMMENTS

The inner function is cosec(x) - coth(x) = -x/6 + x^3/24 - x^5/15120 + 17*x^7/40320 - x^9/23950080 + 691*x^11/159667200 - ...

LINKS

G. C. Greubel, Table of n, a(n) for n = 0..199

EXAMPLE

-x/6 + 55*x^3/1296 - 4219*x^5/6531840 + 802171*x^7/1410877440 - 109684277*x^9/5746705367040 + ...

MATHEMATICA

Numerator[Take[CoefficientList[Series[Sin[Csc[x] - Coth[x]], {x, 0, 25}], x], {2, -1, 2}]] (* G. C. Greubel, Nov 13 2016 *)

CROSSREFS

Sequence in context: A250833 A206097 A103918 * A056567 A119081 A119051

Adjacent sequences:  A013534 A013535 A013536 * A013538 A013539 A013540

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 7 13:08 EST 2021. Contains 349581 sequences. (Running on oeis4.)