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 A193841 #7 Jun 07 2017 12:46:31 %S A193841 2,4,7,12,10,15,23 %N A193841 Erroneous version of A227590. %K A193841 dead %O A193841 2,1