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 A065252 #6 Jul 30 2017 23:21:21 %S A065252 1,1,0,1,0,2,1,1,0,2,1,0,2,1,0,1,0,2,1,0,2,1,0,2,1,0,2,1,0,2,1,1,0,2, %T A065252 1,0,2,1,0,2,1,0,2,1,0,2,1,0,2,1,0,2,1,0,2,1,0,2,1,0,2,1,0,1,0,2,1,0, %U A065252 2,1,0,2,1,0,2,1,0,2,1,0,2,1,0,2,1,0,2,1,0,2,1,0,2,1,0,2,1,0,2,1,0,2,1,0,2 %N A065252 The sequence A065251 reduced modulo 3 (i.e., replace every -1 with 2). %F A065252 a(0)=0, a(2n) = 2 - a(n), a(2n+1) = 2 - ((a(n)+1) mod 3). %p A065252 [seq((A065251(j) mod 3),j=1..120)]; %K A065252 nonn %O A065252 1,6 %A A065252 _Antti Karttunen_, Oct 25 2001