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 A334766 #11 May 14 2020 01:23:08 %S A334766 1,2,4,12,6,3,9,18,36,144,48,16,80,20,10,5,15,30,60,180,90,45,225,75, %T A334766 25,50,100,300,150,450,900,3600,720,240,1200,400,2800,560,112,28,14,7, %U A334766 21,42,84,252,126,63,315,105,35,70,140,420,210,630,1260,5040,1008 %N A334766 Lexicographically earliest sequence of distinct positive integers such that for any n > 0, the prime tower factorization of a(n+1) can be obtained from that of a(n) by adding or removing exactly one prime number. %C A334766 The prime tower factorization of a number is defined in A182318. %C A334766 For any n > 0, a(n+1) is either a multiple or a divisor of a(n). %C A334766 For any prime number p, the sequence contains a multiple of p. %H A334766 Rémy Sigrist, <a href="/A334766/b334766.txt">Table of n, a(n) for n = 1..10000</a> %H A334766 Rémy Sigrist, <a href="/A334766/a334766.gp.txt">PARI program for A334766</a> %F A334766 abs(A106490(a(n+1)) - A106490(a(n))) = 1. %e A334766 The first terms, alongside their prime tower factorizations, are: %e A334766 n a(n) Prime tower factorization of a(n) %e A334766 -- ---- --------------------------------- %e A334766 1 1 1 %e A334766 2 2 2 %e A334766 3 4 2^2 %e A334766 4 12 2^2 * 3 %e A334766 5 6 2 * 3 %e A334766 6 3 3 %e A334766 7 9 3^2 %e A334766 8 18 2 * 3^2 %e A334766 9 36 2^2 * 3^2 %e A334766 10 144 2^2^2 * 3^2 %e A334766 11 48 2^2^2 * 3 %e A334766 12 16 2^2^2 %e A334766 13 80 2^2^2 * 5 %e A334766 14 20 2^2 * 5 %e A334766 15 10 2 * 5 %e A334766 16 5 5 %o A334766 (PARI) See Links section. %Y A334766 Cf. A106490, A182318, A298480. %K A334766 nonn %O A334766 1,2 %A A334766 _Rémy Sigrist_, May 10 2020