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A013556 Numerator of [x^(2n)] of the Taylor series cos(cot(x)-coth(x))= 1 -2*x^2/9 +2*x^4/243 -676*x^6/229635 +62*x^8/295245 -... 1
1, -2, 2, -676, 62, -2714132, 7223932, -120994136, 13831453742, -463898158095404, 1539871314859772, -1284535259155106488, 5072225817430199548, -10084534723769793975176, 4033550950013006300665768, -325181210925396330786544500464, 435279229771188834270330121078 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 0..200

MATHEMATICA

Numerator[Take[CoefficientList[Series[Cos[Cot[x] - Coth[x]], {x, 0, 35}], x], {1, -2, 2}]] (* Vincenzo Librandi, Nov 12 2016 *)

CROSSREFS

Sequence in context: A262058 A067091 A334599 * A093596 A095304 A111819

Adjacent sequences:  A013553 A013554 A013555 * A013557 A013558 A013559

KEYWORD

sign,frac

AUTHOR

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

EXTENSIONS

Name edited by R. J. Mathar, Dec 22 2011

STATUS

approved

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Last modified December 7 13:08 EST 2021. Contains 349581 sequences. (Running on oeis4.)