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 A026339 #4 Mar 30 2012 18:56:06 %S A026339 1,3,4,6,8,9,11,12,15,16,18,20,21,22,24,26,27,29,30,33,35,36,38,39,42, %T A026339 43,45,47,48,49,51,52,54,56,57,60,61,62,63,66,67,69,70,72,75,76,78,80, %U A026339 81,83,84,87,88,89,90,93,96,97,98,99,102,103 %N A026339 a(n) = least k such that s(k) = n, where s = A026338. %K A026339 nonn %O A026339 1,2 %A A026339 _Clark Kimberling_