login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 59th year, we have over 358,000 sequences, and we’ve crossed 10,300 citations (which often say “discovered thanks to the OEIS”).

Other ways to Give
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A012867 Numerators of coefficients in Taylor series expansion of log(cotan(x)*arctan(x)). 2
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

Vincenzo Librandi, Table of n, a(n) for n = 0..250

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: A098879 A331818 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

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified December 10 02:09 EST 2022. Contains 358712 sequences. (Running on oeis4.)