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 A181663 #18 Mar 30 2012 16:51:58 %S A181663 1,0,0,0,0,1,0,0,1,0,0,1,0,0,1,0,0,1,0,0,1,0,0,1,0,0,1,0,0,1,0,0,1,0, %T A181663 0,0,0,0,0,1,0,0,0,0,0,1,0,0,0,0,1,0,0,1,0,0,1,0,0,1,0,0,0,0,1,0,0,1, %U A181663 0,0,1,0,0,0,1,0,0,0,0,0,1,0,0,1,0,0,1,0,0,0,1,0,0,1,0,0,0,1,0,0,1,0,0,0,1,0,0,1,0,0,0,0,0,0,1,0,0,0,1,0,0,0,0,1 %N A181663 a(n) = A105801(n) mod 2. %H A181663 N. J. A. Sloane, <a href="/A181663/b181663.txt">Table of n, a(n) for n = 1..3000</a> %Y A181663 Cf. A105801 %K A181663 nonn %O A181663 1,1 %A A181663 _N. J. A. Sloane_, Nov 20 2010