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 A061307 #2 Feb 24 2006 03:00:00 %S A061307 1,1,2,12,360,55440,61261200,293318625600,6064949221531200 %N A061307 Duplicate of A061300. %K A061307 dead %O A061307 0,3