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%I #9 Jun 24 2024 17:16:03
%S 1,1,2,3,24,15,360,5040,40320,11340,1814400,39916800,47900160,
%T 6227020800,7925299200,1307674368000,20922789888000,11115232128000,
%U 3201186852864000,24329020081766400,48658040163532800,51090942171709440000,1124000727777607680000,5170403347776995328000
%N Denominators in Taylor series expansion of Product_{n >= 1} (1+x^n/n!).
%H H. Gingold, H. W. Gould, and M. E. Mays, <a href="https://www.researchgate.net/publication/268023169_Power_product_expansions">Power product expansions</a>, Util. Math., 34 (1988), 143-161.
%e 1 + x + (1/2)*x^2 + (2/3)*x^3 + (5/24)*x^4 + (2/15)*x^5 + (41/360)*x^6 + (169/5040)*x^7 + ...
%t nmax=23; Denominator[CoefficientList[Series[Product[ (1+x^n/n!),{n,nmax}],{x,0,nmax}],x]] (* _Stefano Spezia_, Jun 24 2024 *)
%Y Cf. A170908.
%K nonn,frac
%O 0,3
%A _N. J. A. Sloane_, Jan 30 2010
%E a(23) from _Stefano Spezia_, Jun 24 2024