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 A031053 #4 Mar 30 2012 18:56:20 %S A031053 7,22,38,54,70,86,102,105,107,109,111,113,115,117,118,119,141,165,189, %T A031053 213,237,261,285,289,292,295,298,301,304,307,309,310,333,357,381,405, %U A031053 429,453,477,481,484,487,490,493,496,499,501 %N A031053 Position of n-th 7 in A031045. %K A031053 nonn %O A031053 1,1 %A A031053 _Clark Kimberling_