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 A043704 #8 Jun 18 2021 22:37:26 %S A043704 15,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,33,34,35,36,37,38,39, %T A043704 40,41,42,43,44,45,46,47,49,50,51,52,53,54,55,56,57,58,59,60,61,62,63, %U A043704 65,66,67,68,69,70,71,72,73,74,75,76,77,78 %N A043704 Numbers whose base-15 representation has an even number of runs. %K A043704 nonn,base %O A043704 1,1 %A A043704 _Clark Kimberling_