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 A064620 #3 May 11 2007 03:00:00 %S A064620 1,2,3,5,4,7,11,6,13,17,10,19,9,8,23,29,14,15,31,22,37,41,12,43,25,26 %N A064620 Duplicate of A064216. %K A064620 dead %O A064620 1,2