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 A066587 #2 Sep 29 2006 03:00:00 %S A066587 3,5,11,13,19,21,27,29,35,37,43,45,51,53,59,61,67,69,75,77,83,85,91,93 %N A066587 Duplicate of A047621. %K A066587 dead %O A066587 1,1