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 A050105 #4 Mar 30 2012 18:57:01 %S A050105 1,4,2,7,14,5,28,19,3,42,17,8,24,40,15,47,72,6,38,13,29,45,70,20,61, %T A050105 36,11,77,27,43,68,136,18,127,34,9,152,75,25,143,100,41,168,91,16,159, %U A050105 32,48,322,150,73,399,528,23,98,64,39,338,89 %N A050105 a(n)=position of n in A050104. %K A050105 nonn %O A050105 1,2 %A A050105 _Clark Kimberling_