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 A221670 #4 Jan 22 2013 01:30:52 %S A221670 23,205,289,373,425,527,565 %N A221670 Seven numbers whose squares are among the entries in a 3 x 3 magic square. %C A221670 The entries of the magic square are A221669. See there for references, links, formulas, and additional comments. %Y A221670 Cf. A221669. %K A221670 nonn,fini,full %O A221670 1,1 %A A221670 _Jonathan Sondow_, Jan 21 2013