The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 Please make a donation to keep the OEIS running. We are now in our 56th year. In the past year we added 10000 new sequences and reached almost 9000 citations (which often say "discovered thanks to the OEIS"). Other ways to donate

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A156036 Numerators in expansion of log(z^2/(cosh(z)-cos(z))). 3
 0, -1, 1, -691, 3617, -174611, 236364091, -3392780147, 7709321041217, -26315271553053477373, 261082718496449122051, -2530297234481911294093, 5609403368997817686249127547, -61628132164268458257532691681, 354198989901889536240773677094747, -1215233140483755572040304994079820246041491 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,4 REFERENCES V. Mangulis, Handbook of Series, Academic Press, 1965, p. 76. LINKS FORMULA log(z^2/(cosh(z)-cos(z))) = Sum_{ n >= 1 } (-1)^n*B_{2n}*(2z^2)^(2n)/((4n)!2n). a(n)=Numerator((-1)^n * Zeta(4n)/(Zeta(2n)*Pi^(2n)). - Enrique Pérez Herrero, Jun 20 2012 EXAMPLE log(z^2/(cosh(z)-cos(z))) = -(1/360)*z^4+(1/302400)*z^8-(691/122594472000)*z^12+(3617/333456963840000)*z^16+... CROSSREFS Cf. A156032. Sequence in context: A046753 A033563 A231273 * A029814 A135843 A130662 Adjacent sequences:  A156033 A156034 A156035 * A156037 A156038 A156039 KEYWORD sign,frac AUTHOR N. J. A. Sloane, Oct 31 2009 STATUS approved

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

Last modified December 3 20:56 EST 2020. Contains 338920 sequences. (Running on oeis4.)