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 A082142 #4 May 11 2007 03:00:00 %S A082142 1,2,12,80,560,4032,29568,219648,1647360,12446720,94595072,722362368 %N A082142 Duplicate of A069723. %K A082142 dead %O A082142 1,2