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 A089104 #42 Dec 19 2017 22:49:34 %S A089104 1,2,8,50,432,4802,65536,1062882,20000000,428717762 %N A089104 Duplicate of A007334. %K A089104 dead %O A089104 2,2