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 A030573 #4 Mar 30 2012 18:56:18 %S A030573 5,16,28,40,52,55,57,59,61,63,64,65,81,99,117,135,153,157,160,163,166, %T A030573 169,171,172,189,207,225,243,261,265,268,271,274,277,279,280,297,315, %U A030573 333,351,369,373,376,379,382,385,387,388,405 %N A030573 Position of n-th 5 in A030567. %K A030573 nonn %O A030573 1,1 %A A030573 _Clark Kimberling_