%I #11 Apr 14 2024 08:45:11
%S 1,1,1,1,1,2,6,8,40,720,560,4480,362880,1209600,13305600,479001600,
%T 188697600,2641766400,1307674368000,774918144000,1197600768000,
%U 44771844096000,3119105138688000,73724303278080000,4644631106519040000,374666909259202560000,8617338912961658880000
%N Denominator of (-1)^n*n!*(E(n,2)-E(n,1)*E(n-1,1)) where E(n,x) = Sum_{k=0..n} (-1)^k*x^k/k!.
%e 1, 1, 2, 3, 5, 17/2, 89/6, 211/8, 1903/40, 62473/720, ...
%t e[n_,x_]:=Sum[(-x)^k/k!,{k,0,n}]; a[n_]:=Denominator[(-1)^n*n!*(e[n,2]-e[n,1]e[n-1,1])]; Array[a,27,0] (* _Stefano Spezia_, Apr 12 2024 *)
%Y Cf. A065952 (numerator), A065954, A065955, A065956.
%K nonn,frac
%O 0,6
%A _N. J. A. Sloane_, Dec 08 2001
%E a(0)=1 prepended by and a(25)-a(26) from _Stefano Spezia_, Apr 12 2024