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 A115237 #3 Mar 30 2012 17:37:16 %S A115237 1,2,1,4,4,1,6,8,4,1,9,14,10,4,1,12,20,18,10,4,1,16,28,29,20,10,4,1, %T A115237 20,36,41,33,20,10,4,1,25,46,56,50,35,20,10,4,1,30,56,71,69,54,35,20, %U A115237 10,4,1,36,68,89,92,78,56,35,20,10,4,1,42,80,107,116,105,82,56,35,20,10,4,1 %N A115237 Matrix square of triangle A003983. %e A115237 1; 2,1; 4,4,1; 6,8,4,1; 9,14,10,4,1; ... %Y A115237 Column 0: A002620(n+2). Row sums: A115238. Convergent of columns: A000292. %K A115237 nonn,tabl %O A115237 0,2 %A A115237 _Christian G. Bower_, Jan 17 2006