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 A031112 #4 Mar 30 2012 18:56:20 %S A031112 15,19,46,52,66,69,77,102,105,115,117,118,134,146,151,153,156,171,172, %T A031112 181,183,191,197,206,222,239,246,250,261,264,267,270,273,290,299,301, %U A031112 316,317,326,330,332,336,344,372,394,409,420 %N A031112 Position of n-th 0 in A031111. %K A031112 nonn %O A031112 1,1 %A A031112 _Clark Kimberling_