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 A013554 Numerator of [x^(2n+1)] in the Taylor expansion -tan(cot(x)-coth(x))= 2*x/3 +8*x^3/81 +556*x^5/25515 +496*x^7/98415 +717572*x^9/613814355 +... 1

%I

%S 2,8,556,496,717572,52939408,870202072,964225030112,657454597470988,

%T 27485377040128048,700808303776317525176,1479866177061564649568,

%U 1640650015131154843789016,13376815891310731844679270304,25395222315410089406698868631728

%N Numerator of [x^(2n+1)] in the Taylor expansion -tan(cot(x)-coth(x))= 2*x/3 +8*x^3/81 +556*x^5/25515 +496*x^7/98415 +717572*x^9/613814355 +...

%H Vincenzo Librandi, <a href="/A013554/b013554.txt">Table of n, a(n) for n = 0..100</a>

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

%K nonn,frac

%O 0,1

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

%E Name edited by _R. J. Mathar_, Dec 21 2011

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