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 A185631 #10 May 03 2025 22:26:33
%S A185631 1,4,10,32,137,766,5382,46022,467206,5519252,74629263,1139283601,
%T A185631 19411643752,365595475542,7548810986515,169681672611815,
%U A185631 4126880020198630,108026180912533227,3029184083924476085,90617948406514693702,2881333799993441893564,97057552263114611503090
%N A185631 Row sums of triangle A185628.
%C A185631 Triangle A185628 equals the matrix cube of triangle R = A185620, which satisfies: R^3 - R^2 + I = R shifted left one column.
%o A185631 (PARI) {a(n)=local(A=Mat(1), B); for(m=1, n+1, B=A^3-A^2+A^0; A=matrix(m+1, m+1); for(i=1, m+1, for(j=1, i, if(i<2||j==i, A[i, j]=1, if(j==1, A[i, j]=1, A[i, j]=B[i-1, j-1]))))); return(sum(k=1,n+1,(A^3)[n+1, k]))}
%Y A185631 Cf. A185620, A185628, A185629, A185630.
%K A185631 nonn
%O A185631 0,2
%A A185631 _Paul D. Hanna_, Sep 07 2011