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 A083369 #4 Nov 10 2007 03:00:00 %S A083369 1,2,3,7,43,139,50207,340999,2365347734339,4680225641471129, %T A083369 1368845206580129 %N A083369 Essentially a duplicate of A000946. %K A083369 dead %O A083369 1,2