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%I #13 Sep 06 2018 11:10:49
%S 1,3,5,315,567,51975,19305,212837625,2127125,371231385525,
%T 17717861581875,1095751306274625,284473896821296875,
%U 185436341599368234375,184915818535229656875,8168656283793770092453125,5285601124807733589234375,5940428375270025028345078125
%N Denominators of fractions converging to limiting value of Fekete polynomials.
%H Lars Blomberg, <a href="/A280035/b280035.txt">Table of n, a(n) for n = 1..25</a>
%H Christian Günther, Kai-Uwe Schmidt, <a href="http://arxiv.org/abs/1602.01750">L^q norms of Fekete and related polynomials</a>, arXiv:1602.01750 [math.NT], 2016
%e 1/1, 5/3, 19/5, 3469/315, 21565/567, 7760593/51975, 12478099/19305, 643983856759/212837625,
%t (* "gen" stands for "generalized Eulerian number" *)
%t gen[n_, x_] := Sum[(-1)^j Binomial[n + 1, j] (x + 1 - j)^n, {j, 0, Floor[x + 1]}];
%t T[k_] := T[k] = 1 - Sum[Binomial[2 k - 1, 2 j - 1] T[j], {j, 1, k - 1}];
%t F[0, 0] = 1; F[k_, m_] /; 1 <= m <= 2 k - 1 := F[k, m] = Sum[Binomial[2 k - 1, 2 j - 1] T[j]/(2 j - 1)! Sum[gen[2 j - 1, i - 1] F[k - j, m - i], {i, 0, m}], {j, 1, k}]; F[_, _] = 0;
%t Table[F[k, k] // Denominator, {k, 1, 18}] (* _Jean-François Alcover_, Sep 06 2018 *)
%Y Cf. A280034. Related to central column of array in A280033.
%K nonn,frac
%O 1,2
%A _N. J. A. Sloane_, Dec 28 2016
%E More terms from _Lars Blomberg_, Jun 14 2017
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