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A012861 Numerator of the coefficient of [x^(2n)] of the Taylor series log(cosec(x)*arctanh(x))= x^2/2 +3*x^4/20 +4*x^6/45 +203*x^8/3240 +2038*x^10/42525 +... 1
1, 3, 4, 203, 2038, 319561, 61425307, 8552625673, 11620410478, 16155306808034, 1810024463827637, 147005475101499533, 139995370486066058107, 7441717839455761431719, 66171433716055691335387 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

The inner function is cosec(x)*arctanh(x) = 1+ x^2/2 +11*x^4/40 +133*x^6/720 +36211*x^8/259200 +1226971*x^10/10886400 +...

LINKS

Table of n, a(n) for n=1..15.

CROSSREFS

Cf. A202602 (denominators)

Sequence in context: A042081 A245456 A042275 * A042485 A111315 A042711

Adjacent sequences:  A012858 A012859 A012860 * A012862 A012863 A012864

KEYWORD

nonn,frac

AUTHOR

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

EXTENSIONS

Values replaced by numerators. - R. J. Mathar, Dec 20 2011

STATUS

approved

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Last modified December 9 19:51 EST 2019. Contains 329879 sequences. (Running on oeis4.)