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 A025241 #1 Dec 11 1999 03:00:00 %S A025241 1,1,1,1,2,4,8,17,37,82,185,423,978,2283,5373,12735,30372,72832,175502 %N A025241 Essentially same as A004148. %K A025241 dead %O A025241 1,5