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 A113955 #3 Mar 30 2012 18:59:12
%S A113955 1,3,1,11,6,1,42,30,9,1,163,140,58,12,1,638,630,325,95,15,1,2510,2772,
%T A113955 1686,624,141,18,1,9908,12012,8330,3682,1064,196,21,1,39203,51480,
%U A113955 39796,20264,7050,1672,260,24,1,155382,218790,185517,106203,42849,12303,2475
%N A113955 Riordan array (1/((1-4x)c(x)),xc(x)/sqrt(1-4x)), c(x) the g.f. of A000108.
%C A113955 Columns include A032443,A002457,A018218,A038836. Row sums are A100192. Diagonal sums are A113956.
%F A113955 Riordan array ((1/(1-4x)+1/sqrt(1-4x))/2, (2x/((1-4x)+sqrt(1-4x)))); Number triangle T(n, k)=sum{j=0..n, C(j, j-k)C(2n, n-j)}.
%F A113955 T(n,k)=sum{j=0..n, C(2n,j)C(n-j,k)}; - _Paul Barry_, Apr 03 2006
%e A113955 Triangle begins
%e A113955 1;
%e A113955 3, 1;
%e A113955 11, 6, 1;
%e A113955 42, 30, 9, 1;
%e A113955 163, 140, 58, 12, 1;
%e A113955 638, 630, 325, 95, 15, 1;
%K A113955 easy,nonn,tabl
%O A113955 0,2
%A A113955 _Paul Barry_, Nov 09 2005