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%I #11 Nov 12 2016 08:12:11
%S 1,-2,2,-4,2,-136,676,-656,62,-47672,2714132,-3091664,7223932,
%T -16788784,120994136,-15764283616,13831453742,-3729134588968,
%U 463898158095404,-119174509180016
%N Numerator of [x^n] in the Taylor expansion exp(cot(x)-coth(x))= 1-2*x/3 +2x^2/9 -4*x^3/81 +2*x^4/243 -136*x^5/25515 +676*x^6/229635 -...
%C The inner function is cot(x)-coth(x) = -2x/3 -4x^5/945 -4x^9/93555 -8x^13/18243225 -...
%H Harvey P. Dale, <a href="/A013551/b013551.txt">Table of n, a(n) for n = 0..485</a>
%t Numerator[CoefficientList[Series[Exp[Cot[x]-Coth[x]],{x,0,20}],x] ] (* _Harvey P. Dale_, Feb 16 2014 *)
%K sign,frac
%O 0,2
%A Patrick Demichel (patrick.demichel(AT)hp.com)
%E Name edited by _R. J. Mathar_, Dec 21 2011