%I #13 Jul 14 2024 16:15:32
%S 1,3,3,90,18,945,1890,12600,22680,53460,1247400,10216206000,157172400,
%T 1021620600,6129723600,534386160000,81729648000,2494674910728000,
%U 127932046704000,2744142401800800000
%N Denominators of expansion of exp x / sin x.
%H Robert Israel, <a href="/A007451/b007451.txt">Table of n, a(n) for n = 0..70</a>
%p c:= proc(m) option remember;
%p 1/(m+1)! - add((-1)^i/(2*i+1)!*c(m-2*i),i=1..floor((m+1)/2))
%p end proc;
%p c(-1):= 1;
%p A007451:= denom @ c; # _Robert Israel_, Apr 13 2014
%t Denominator[CoefficientList[Series[Exp[x]/Sin[x],{x,0,20}],x]]//Quiet (* _Harvey P. Dale_, Mar 16 2018 *)
%Y Cf. A007418.
%K nonn,frac
%O 0,2
%A _N. J. A. Sloane_.