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 A030608 #4 Mar 30 2012 18:56:19 %S A030608 3,9,10,14,35,37,48,57,66,70,83,84,90,91,99,110,142,143,146,147,149, %T A030608 153,160,166,191,194,197,204,206,216,219,222,226,236,237,250,259,260, %U A030608 261,262,263,266,268,269,272,287,309,312,315,319 %N A030608 Position of n-th 3 in A030604. %K A030608 nonn %O A030608 1,1 %A A030608 _Clark Kimberling_