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 A050133 #4 Mar 30 2012 18:57:01 %S A050133 1,10,3,14,9,2,6,13,29,8,17,4,20,42,5,12,25,53,28,57,7,16,33,69,36,73, %T A050133 19,78,41,85,22,45,11,24,49,101,52,105,27,56,114,230,60,121,15,32,65, %U A050133 133,68,137,35,72,146,18,38,77,157,40,81,165 %N A050133 a(n)=least k satisfying a(k)=n in A050132. %K A050133 nonn %O A050133 1,2 %A A050133 _Clark Kimberling_