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 A146520 #4 Dec 18 2015 18:17:15 %S A146520 4,64,34120,15748194,7568305274,4203938567056 %N A146520 Number of n X n arrays of squares of integers summing to 26 with every element equal to at least one neighbor. %K A146520 nonn %O A146520 2,1 %A A146520 _R. H. Hardin_ Apr 14 2009