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 A124468 #3 Mar 30 2012 18:37:01
%S A124468 1,3,13,73,506,4117,37703,378529,4106995,47766886,592228264,
%T A124468 7791350900,108323265571,1585742194947,24364012940723,391780319558565,
%U A124468 6577005078357973,115010285695135090,2090723838361780991
%N A124468 Secondary diagonal of rectangular table A124460.
%C A124468 In table A124460, the g.f. of row n, R_n(y), simultaneously satisfies: R_n(y) = Sum_{k>=0} y^k * R_k(y)^n for n>=0.
%o A124468 (PARI) {a(n)=local(R=vector(n+2,r,vector(n+1,c,binomial(r+c-2,c-1)))); for(i=0,n+1,for(r=0,n+1,R[r+1]=Vec(sum(c=0,n,x^c*Ser(R[c+1])^r+O(x^(n+2))))));R[n+2][n+1]}
%Y A124468 Cf. A124460 (table); rows: A124461, A124462, A124463, A124464, A124465, A124466; A124467 (diagonal).
%K A124468 nonn
%O A124468 0,2
%A A124468 _Paul D. Hanna_, Nov 03 2006