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 A161431 #2 Mar 30 2012 17:34:00 %S A161431 9,24,24,66,24 %N A161431 First differences of A161430. %Y A161431 Cf. A139251, A160121, A161430, A161432, A161433. %K A161431 more,nonn %O A161431 1,1 %A A161431 _Omar E. Pol_, Jun 17 2009