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 A202781 #10 May 11 2020 19:21:07 %S A202781 6,36,2442,4756140,255657603186 %N A202781 Duplicate of A067213. %K A202781 dead %O A202781 1,1