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 A209425 #7 Jul 01 2025 15:24:18
%S A209425 1,12,347,20429,1919660,259227625,47484618291,11331926690549,
%T A209425 3416394867284954,1269892206580345425,570576180005762038644,
%U A209425 304859737124260849580998,191049110542296621467314753,138786261071300963667336947034,115691448070469092032508527982414
%N A209425 Column 2 of triangle A209424.
%o A209425 (PARI) {a(n)=polcoeff(polcoeff(exp(sum(m=1,n,x^m/m*sum(k=0,m,binomial(m,k)^m*y^k))+x*O(x^n)),n,x),2,y)}
%o A209425 for(n=0,20,print1(a(n),", "))
%Y A209425 Cf. A209424, A209426.
%K A209425 nonn
%O A209425 2,2
%A A209425 _Paul D. Hanna_, Mar 08 2012