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 A026212 #10 Feb 05 2020 07:32:44 %S A026212 1,3,5,2,9,11,4,15,6,7,21,23,8,27,10,33,12,13,39,41,14,45,47,16,17,51, %T A026212 18,19,57,59,20,63,22,69,24,25,75,77,26,81,28,29,87,30,31,93,95,32,99, %U A026212 101,34,35,105,36,37,111,113,38,117 %N A026212 Duplicate of A026188. %K A026212 dead %O A026212 1,2