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 A013555 Numerator of [x^(2n+1)] of the Taylor series arctan(cot(x)-coth(x))= -2*x/3 +8*x^3/81 -52*x^5/1701 +112*x^7/10935 -51412*x^9/13640319+... 1

%I

%S -2,8,-52,112,-51412,3469712,-2491688,62534458528,-22811578796,

%T 1052637839125232,-1951793355443020696,1800318713817966304,

%U -132444323199647003032,130585857053193268706729632,-9112129339306147838595664

%N Numerator of [x^(2n+1)] of the Taylor series arctan(cot(x)-coth(x))= -2*x/3 +8*x^3/81 -52*x^5/1701 +112*x^7/10935 -51412*x^9/13640319+...

%H Vincenzo Librandi, <a href="/A013555/b013555.txt">Table of n, a(n) for n = 0..100</a>

%t Numerator[Take[CoefficientList[Series[ArcTan[Cot[x] - Coth[x]], {x, 0, 35}], x], {2, -2, 2}]] (* _Vincenzo Librandi_, Nov 12 2016 *)

%K sign,frac

%O 0,1

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

%E Name edited by _R. J. Mathar_, Dec 22 2011

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Last modified September 25 22:55 EDT 2020. Contains 337346 sequences. (Running on oeis4.)