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 A031305 #4 Mar 30 2012 18:56:21 %S A031305 6,22,42,62,82,102,111,113,115,117,119,121,122,123,125,127,129,142, %T A031305 162,182,208,238,268,298,328,358,371,374,377,380,383,386,388,389,392, %U A031305 395,398,418,448,478,508,538,568,598,628,658,671 %N A031305 Position of n-th 6 in A031298. %K A031305 nonn %O A031305 1,1 %A A031305 _Clark Kimberling_