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 A146504 #4 Dec 18 2015 18:17:14 %S A146504 1,163,44537,12234095,13115315167 %N A146504 Number of n X n arrays of squares of integers with every (n-1)X(n-1) subblock summing to 16 and every element equal to at least one neighbor. %K A146504 nonn %O A146504 3,2 %A A146504 _R. H. Hardin_ Apr 14 2009