%I #8 Dec 10 2016 22:40:17
%S 2,8,48,5760,80640,14515200,958003200,1394852659200,41845579776000,
%T 522642751488000,442345819668480000,8992005822220861440000,
%U 1240896803466478878720000,1613165844506422542336000000,609776689223427721003008000000
%N Denominators of coefficients in expansion of (cos x)/(1 + cos(sqrt(x))).
%H Clark Kimberling, <a href="/A279239/b279239.txt">Table of n, a(n) for n = 0..1000</a>
%e (1/2) + (1/8)x - (11/48)x^2 - (343/5760)x^3 + ... ; 1/2, 1/3, -11/48, 1/6480, -343/5760, ... = A279238/A279239.
%t z = 26; t = CoefficientList[Series[Cos[x]/(1 + Cos[Sqrt[x]]), {x, 0, z}], x];
%t Numerator[t] (* A279238 *)
%t Denominator[t] (* A279239 *)
%t %/2 (* A279240 *)
%Y Cf. A279238, A279240.
%K nonn,easy,frac
%O 0,1
%A _Clark Kimberling_, Dec 08 2016