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 A192723 #18 Sep 11 2019 08:36:17 %S A192723 1,5,55,1077,32951,1451723,87054773,6818444405,675900963271, %T A192723 82717196780955,12248810651651332,2158585005685222202, %U A192723 446445657799551722026,107087164031952012004954 %N A192723 Erroneous version of A102221. %K A192723 dead %O A192723 1,2