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1,2

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 +...

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

Cf. A202602 (denominators)

Sequence in context: A042081 A245456 A042275 * A042485 A111315 A042711

Adjacent sequences: A012858 A012859 A012860 * A012862 A012863 A012864

nonn,frac

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

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

approved