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A012867 Numerators of coefficients in Taylor series expansion of log(cotan(x)*arctan(x)). 1
0, -2, 1, -313, 317, -7813, 6895597, -61916737, 10655226077, -41786390722733, 613552118040217, -41640337444573141, 6761598195684420293, -140000933764069408573, 81775784693678733811, -368555295637618487393608489, 41000094641259185671029500461, -243445658683280857337557514581 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

LINKS

Table of n, a(n) for n=0..17.

EXAMPLE

-2/3*x^2+1/15*x^4-313/2835*x^6+317/5670*x^8-7813/155925*x^10+...

MATHEMATICA

Numerator[Take[CoefficientList[Series[Log[Cot[x]ArcTan[x]], {x, 0, 40}], x], {1, -1, 2}]] Harvey P. Dale, May 18 2012

CROSSREFS

Cf. A202621.

Sequence in context: A016448 A098879 A261437 * A178393 A272538 A087037

Adjacent sequences:  A012864 A012865 A012866 * A012868 A012869 A012870

KEYWORD

sign,frac

AUTHOR

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

EXTENSIONS

Corrected by N. J. A. Sloane, Dec 21 2011

STATUS

approved

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Last modified November 22 05:36 EST 2017. Contains 295076 sequences.