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 A031041 #4 Mar 30 2012 18:56:20 %S A031041 5,19,35,51,67,72,74,76,78,80,82,83,84,86,99,115,137,161,185,209,233, %T A031041 241,244,247,250,253,256,257,259,262,281,305,329,353,377,401,425,433, %U A031041 436,439,442,445,448,449,451,454,473,497,521 %N A031041 Position of n-th 5 in A031035. %K A031041 nonn %O A031041 1,1 %A A031041 _Clark Kimberling_