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 A189709 #6 Mar 30 2012 18:57:25 %S A189709 0,1,2,2,2,3,3,3,4,4,5,6,6,7,8,8,8,9,9,10,11,11,12,13,13,13,14,14,15, %T A189709 16,16,16,17,17,17,18,18,19,20,20,20,21,21,21,22,22,23,24,24,25,26,26, %U A189709 26,27,27,28,29,29,29,30,30,30,31,31,32,33,33,33,34,34,34,35,35,36,37,37,38,39,39,39,40 %N A189709 Partial sums of A189706. %C A189709 See A189706. %F A189709 s(n)=[(n+1)/3]-s([(n+1)/3])+[n/3], where s(0)=0. %t A189709 (See A189706.) %Y A189709 Cf. A189706, A189707, A189708. %K A189709 nonn %O A189709 1,3 %A A189709 _Clark Kimberling_, Apr 25 2011