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%I #11 Jun 04 2019 11:27:44
%S 1,1,3,1,15,1,21,1,15,1,33,1,1365,1,3,1,255,1,399,1,1155,1,69,1,1365,
%T 1,21,1,435,1,7161,1,19635,1,21,1,959595,1,21,1,47355,1,9933,1,2415,1,
%U 987,1,23205,1,33,1,8745,1,4389,1,8265,1,177,1,28393365,1,33
%N a(n) = denominator(n!*[z^n]((cosh(x*z) + cos(x*z))*z/(1 - exp(-z)))(1)).
%F a(2*n + 1) = 1 for n >= 0.
%F 3 divides a(2*n) for n >= 1.
%p gf := (cosh(x*z)+cos(x*z))*z/(1-exp(-z)): ser := series(gf, z, 70):
%p seq(denom(subs(x=1, n!*coeff(ser, z, n))), n=0..62);
%t m = 62;
%t gf = (Cosh[x*z] + Cos[x*z])*z/(1 - E^-z);
%t Denominator[CoefficientList[(gf/.x->1)+O[z]^(m+1),z]*Range[0,m]!] (* _Jean-François Alcover_, Jun 04 2019 *)
%Y Cf. A318141 (numerators).
%K nonn,frac
%O 0,3
%A _Peter Luschny_, Aug 19 2018
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