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 A075575 #4 May 11 2007 03:00:00 %S A075575 1,6,55,28,3,10,21,136,15,406,171,820,91,36,595,66,703,120,253,78,1225 %N A075575 Duplicate of A073655. %K A075575 dead %O A075575 1,2