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 A171939 #3 Mar 30 2012 17:28:13 %S A171939 1,2,7370,4,142,7,422,40,26 %N A171939 Position in A171922 at which n first appears, or 0 if n never appears. %H A171939 Hugo van der Sanden, <a href="/A171939/a171939.txt">Table of n, a(n) for n = 1..200, with -1 if n has not yet been found</a> %K A171939 nonn,more %O A171939 1,2 %A A171939 _Hugo van der Sanden_, Oct 23 2010, Oct 24 2010