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A013530 Numerator of [x^(2n+1)] of the Taylor expansion sin(cosec(x) - cosech(x)) = x/3 - x^3/162 + 211*x^5/51030 -157*x^7/688905 + 439801*x^9/9821029680 - ... 1
1, -1, 211, -157, 439801, -8013839, 890107609, -1552280998637, 76919615326361, -25930051873454543, 659157886816533334709, -1513017447627551117359, 6612344442139455641066609, -112537977176478238359834596179 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

COMMENTS

Essentially a bisection of A013529.

LINKS

G. C. Greubel, Table of n, a(n) for n = 0..125

MATHEMATICA

Select[Numerator[CoefficientList[Series[Sin[1/Sin[x]  - 1/Sinh[x]], {x, 0, 25}], x]], # != 0 &] (* G. C. Greubel, Nov 11 2016 *)

CROSSREFS

Cf. A068917.

Sequence in context: A028677 A114442 A037272 * A020365 A031780 A036232

Adjacent sequences:  A013527 A013528 A013529 * A013531 A013532 A013533

KEYWORD

sign,frac

AUTHOR

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

EXTENSIONS

Name edited by R. J. Mathar, Dec 20 2011

STATUS

approved

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Last modified December 6 12:54 EST 2016. Contains 278781 sequences.