This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A362244 #11 Dec 27 2024 16:13:32 %S A362244 1,1,2,12,60,440,3810,37212,430696,5482080,78252390,1227201140, %T A362244 20955546348,388492703040,7745445183658,165550236166980, %U A362244 3773990094033360,91401848785134272,2344168680183033678,63455096201600595060,1808160553359068792020 %N A362244 Expansion of e.g.f. 1/(1 - x * exp(-x * (exp(-x) - 1))). %F A362244 a(n) = n! * Sum_{i=0..n} (-1)^(n-i) * ( Sum_{j=0..n-i} i^j * Stirling2(n-i-j,j)/(n-i-j)! ). %t A362244 With[{nn=20},CoefficientList[Series[1/(1-x Exp[-x(Exp[-x]-1)]),{x,0,nn}],x] Range[0,nn]!] (* _Harvey P. Dale_, Dec 27 2024 *) %o A362244 (PARI) my(N=30, x='x+O('x^N)); Vec(serlaplace(1/(1-x*exp(-x*(exp(-x)-1))))) %Y A362244 Cf. A362245, A362246, A362247. %Y A362244 Cf. A362237. %K A362244 nonn %O A362244 0,3 %A A362244 _Seiichi Manyama_, Apr 12 2023