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 A116729 #13 Apr 12 2016 00:31:56 %S A116729 1,2,5,12,22,34,48,64,82,102,124,148,174,202,232,264,298,334,372,412, %T A116729 454,498,544,592,642,694,748,804,862,922 %N A116729 Duplicate of A048840. %K A116729 dead %O A116729 0,2