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 A330590 #24 Dec 23 2019 06:01:22 %S A330590 2,4,2,2,6,2,8,2,8,2,2,12,2,8,2,8,2,16,2,8,2,2,18,2,20,2,8,2,8,2,24,2, %T A330590 20,2,8,2,2,12,2,24,2,20,2,8,2,8,2,16,2,24,2,20,2,8,2,2,12,2,20,2,24, %U A330590 2,20,2,8,2,32,2,16,2,24,2,24,2,20,2,8,2,2,72 %N A330590 Triangle read by rows: T(n,k) is the number of positive integers m dividing x^n - x^k for all integers x, 0 < k < n. %H A330590 Peter Kagey, <a href="/A330590/b330590.txt">Table of n, a(n) for n = 2..10012</a> (first 141 rows, flattened) %F A330590 T(n,k) = A000005(A330541(n,k)). %F A330590 Conjecture: T(n,1) = 2^A067513(n-1). %e A330590 Table begins: %e A330590 n\k| 1 2 3 4 5 6 7 8 9 10 11 %e A330590 ---+------------------------------------------------- %e A330590 2 | 2; %e A330590 3 | 4, 2; %e A330590 4 | 2, 6, 2; %e A330590 5 | 8, 2, 8, 2; %e A330590 6 | 2, 12, 2, 8, 2; %e A330590 7 | 8, 2, 16, 2, 8, 2; %e A330590 8 | 2, 18, 2, 20, 2, 8, 2; %e A330590 9 | 8, 2, 24, 2, 20, 2, 8, 2; %e A330590 10 | 2, 12, 2, 24, 2, 20, 2, 8, 2; %e A330590 11 | 8, 2, 16, 2, 24, 2, 20, 2, 8, 2; %e A330590 12 | 2, 12, 2, 20, 2, 24, 2, 20, 2, 8, 2. %e A330590 For n=4 and k=2, the sequence x^4 - x^2 evaluated on the positive (equivalently, negative) integers is 0,12,72,240,600,1260,2352,4032,6480,9900,... and all terms are divisible by the following T(4,2) = 6 positive integers: 1, 2, 3, 4, 6, and 12. %Y A330590 Cf. A000005, A330541. %K A330590 nonn,tabl %O A330590 2,1 %A A330590 _Peter Kagey_, Dec 18 2019