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 A030378 #4 Mar 30 2012 18:56:18 %S A030378 1,2,3,4,6,1,10,12,9,16,2,20,3,11,19,28,4,34,37,33,6,7,49,52,8,15,1, %T A030378 64,50,10,73,76,53,12,85,36,48,14,9,84,59,16,17,112,2,110,18,124,65, %U A030378 113,20,3,39,51,22,11,71,99,24,19,26,74,122,172 %N A030378 Least k such that base 4 representation of n begins at s(k), where s=A030373. %K A030378 nonn %O A030378 1,2 %A A030378 _Clark Kimberling_