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 A064581 #3 Nov 10 2007 03:00:00 %S A064581 1,1,1,1,2,2,1,3,5,5,1,4,9,14,13,1,5,14,28,40,36,1,6,20,48,87,118,104 %N A064581 Duplicate of A064580. %K A064581 dead %O A064581 0,5