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 A030750 #4 Mar 30 2012 18:56:19 %S A030750 2,4,5,1,8,12,20,17,23,34,52,31,54,40,66,81,51,139,63,115,136,78,160, %T A030750 137,95,159,114,183,134,245,212,156,354,243,277,182,313,353,436,211, %U A030750 393,350,242,391,390,275,709,536,311,434,648,349 %N A030750 a(n)=least k such that s(k)=n, where s=A030747. %K A030750 nonn %O A030750 1,1 %A A030750 _Clark Kimberling_