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 A117915 #24 Feb 01 2021 19:24:09 %S A117915 1,1,1,1,2,2,1,3,3,3,1,4,4,5,5,1,5,5,7,8,8,1,6,6,9,11,13,13,1,7,7,11, %T A117915 14,18,21,21,1,8,8,13,27,23,29,34,34,1,9,9,15,20,28,37,47,55,55 %N A117915 Erroneous version of A117501. %K A117915 dead %O A117915 1,5