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 A043554 #1 Dec 11 1999 03:00:00 %S A043554 1,1,2,1,2,3,2,1,2,3,4,3,2,3,2,1,2,3,4,3,4,5,4,3,2,3,4,3 %N A043554 Essentially same as A005811. %K A043554 dead %O A043554 0,3