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 A072770 #2 May 01 2014 02:47:42 %S A072770 1,0,0,1,1,1,1,0,0,1,0,0,1,0,0,0,1,1,1,1,0,0,1,0,1,0,1,0,0,1,0,0,0,0, %T A072770 1,0,0,1,0,0,1,0,0,1,0,1,1,0,0,1,1,0,0,1,1,1,0,0,0,1,1,1,0,0,0,1,1,0, %U A072770 1,0,1,1,1,1,0,1,0,1,1,0,1,1,1,1,1,1,1,1,1,0,1,1,0,1,1,0,1,1,1,1,0,1,1,0,1 %N A072770 Triangle A072768 computed modulo 2. %C A072770 Differs from A071674 first time at the position n=37, where A072770(37) = 0, while A071674(37) = 1. %C A072770 The term a(0)=0 is not explicitly listed here as to get a better looking triangle. %o A072770 (Scheme) (define (A072770 n) (modulo (A072768 n) 2)) %Y A072770 a(n) = (A072769(n) + A071674(n)) mod 2. %K A072770 nonn,tabl %O A072770 1,1 %A A072770 _Antti Karttunen_, Jun 12 2002