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 A126469 #3 Mar 30 2012 18:37:02
%S A126469 1,2,5,41,972,44457,3271312,352087787,52098230423,10141977387056,
%T A126469 2513121624034518,772525844883337679,288558785171538716889,
%U A126469 128760943237115947732171,67665205307818875323789155
%N A126469 Row sums of triangle A126465.
%o A126469 (PARI) {a(n)=local(M=matrix(n+1,n+1,r,c,if(r>=c,binomial((r-1)*r*(r+1)/3!-(c-1)*c*(c+1)/3!,r-c))), N=matrix(n+1,n+1,r,c,if(r>=c,binomial((r-1)*r*(r+1)/3!-(c-1)*c*(c+1)/3!+1,r-c)))); sum(k=0,n,(N*M^-1)[n+1,k+1])}
%Y A126469 Cf. A126465, A126466, A126467, A126468.
%K A126469 nonn
%O A126469 0,2
%A A126469 _Paul D. Hanna_, Dec 27 2006