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 A026230 #6 Mar 30 2012 18:56:05 %S A026230 2,4,6,7,10,12,13,16,18,19,21,22,25,28,30,31,34,36,37,39,40,43,46,48, %T A026230 49,52,54,55,57,58,61,63,64,66,67,70,73,75,76,79,82,84,85,88,90,91,93, %U A026230 94,97,100,102,103,106,108,109,111,112,115,117 %N A026230 a(n) = (1/3)*s(n+1), where s = A026229. %Y A026230 Cf. A026144. [From _R. J. Mathar_, Oct 23 2008] %K A026230 nonn %O A026230 1,1 %A A026230 _Clark Kimberling_