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 A050628 #10 Oct 15 2019 00:03:41 %S A050628 1,16,169,56169,36156169,13361561690409,42133615616904090751725289 %N A050628 a(1) = 1; a(n+1) is next smallest nontrivial square containing a(n) as a substring. %F A050628 a(n) = A050629(n)^2. %Y A050628 Cf. A050629, A048557, A050630, A050632, A050634. %K A050628 nonn,base,more %O A050628 1,2 %A A050628 _Patrick De Geest_, Jul 15 1999 %E A050628 a(7) from _Max Alekseyev_, Feb 15 2012