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 A171112 #8 Jan 19 2021 04:00:11 %S A171112 0,0,21,225,882,2370 %N A171112 Duplicate of A171108. %K A171112 dead %O A171112 1,3