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 A166273 #3 Mar 31 2012 13:21:20 %S A166273 3,3,3,6,6,9,3,6,9,6,12,9,9,9,12,9,6,6,18,0,9,15,9,15,12,15,9,12,15, %T A166273 12,15,12,15,21,18,21,9,9,0,12,24,12,12,15,6,18,15,18,21,24,18,12,18, %U A166273 27,18,24,18,12,12,12,33,21,12,33,12,27,18,21,24,6,33,15,15,24,24,30 %N A166273 Bisection 2n+1 of A165605. %C A166273 Conjecture: a(n) = -3 * A166269(n). %H A166273 A. Karttunen, <a href="/A166273/b166273.txt">Table of n, a(n) for n = 0..16383</a> %Y A166273 a(n) = A165605(A005408(n)). %K A166273 nonn %O A166273 0,1 %A A166273 _Antti Karttunen_, Oct 13 2009