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 A030728 #12 Oct 08 2022 18:29:50 %S A030728 3,1,3,1,2,3,1,2,3,1,2,3,5,6,1,2,3,4,5,6,7,1,2,3,4,5,6,7,8,9,1,2,3,4, %T A030728 5,6,7,8,9,10,12,1,2,3,4,5,6,7,8,9,10,11,12,15,1,2,3,4,5,6,7,8,9,10, %U A030728 11,12,13,15,18,1,2,3,4,5,6,7,8,9,10,11,12,13 %N A030728 The second list after the following procedure: starting with a list [3] and an empty list, repeatedly add the distinct values already in both lists in ascending order to the second list and add the corresponding frequencies of those values to the first list. %H A030728 Sean A. Irvine, <a href="/A030728/b030728.txt">Table of n, a(n) for n = 1..1000</a> %Y A030728 The first list is A030727. %K A030728 nonn %O A030728 1,1 %A A030728 _Clark Kimberling_ %E A030728 Name revised in line with A030778 by _Peter Munn_, Oct 08 2022