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 A103993 #2 May 11 2007 03:00:00 %S A103993 3,5,131,383,797,11411,16061,16361,19391,33533,36263,73037,75557,79397 %N A103993 Duplicate of A088269. %K A103993 dead %O A103993 1,1