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 A121284 #4 Sep 08 2013 13:30:53 %S A121284 1,1,1,2,2,1,6,6,3,2,30,30,15,10,6,240,240,120,80,48,30,3120,3120, %T A121284 1560,1040,624,390,240,65520,65520,32760,21840,13104,8190,5040,3120, %U A121284 2227680,2227680,1113840,742560,445536,278460,171360,106080,65520 %N A121284 Triangle T(n,k), 1<=k<=n, read by rows given by T(n,k) = A003266(n)/A000045(k). %K A121284 nonn,tabl %O A121284 1,4 %A A121284 _Philippe Deléham_, Aug 24 2006