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 A146515 #4 Dec 18 2015 18:17:15 %S A146515 0,92,17216,5077564,1460980380,540147070759,87704130371420 %N A146515 Number of n X n arrays of squares of integers summing to 21 with every element equal to at least one neighbor. %K A146515 nonn %O A146515 2,2 %A A146515 _R. H. Hardin_ Apr 14 2009