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 A075582 #4 May 11 2007 03:00:00 %S A075582 5,11,17,71,107,191,431,1151,2591,139967,472391,786431,995327, %T A075582 57395627,63700991,169869311 %N A075582 Duplicate of A059960. %K A075582 dead %O A075582 1,1