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 A143724 #15 Jun 27 2023 09:24:38 %S A143724 1,1,2,1,0,4,1,2,0,5,1,0,0,0,9,1,2,4,0,0,7,1,0,0,0,0,0,15,1,2,0,5,0,0, %T A143724 0,12,1,0,4,0,0,0,0,0,18,1,2,0,0,9,0,0,0,0,15,1,0,0,0,0,0,0,0,0,0,28, %U A143724 1,2,4,5,0,7,0,0,0,0,0,16 %N A143724 Triangle read by rows, inverse Möbius transform of a diagonalized matrix of A116477. %C A143724 For n-th row of the triangle, the inverse Möbius transform extracts A116477(k) such that k divides n; 0 otherwise. %C A143724 Row sums = A006218: (1, 3, 5, 8, 10, 14, 16, ...). %F A143724 Triangle read by rows, A051731 * (A116477 * 0^(n-k)); 1 <= k <= n. %e A143724 First few rows of the triangle: %e A143724 1; %e A143724 1, 2; %e A143724 1, 0, 4; %e A143724 1, 2, 0, 5; %e A143724 1, 0, 0, 0, 9; %e A143724 1, 2, 4, 0, 0, 7; %e A143724 1, 0, 0, 0, 0, 0, 15; %e A143724 1, 2, 0, 5, 0, 0, 0, 12; %e A143724 ... %e A143724 Example: The divisors of 8 are (1, 2, 4, 8) so row 8 = (1, 2, 0, 5, 0, 0, 0, 12). %Y A143724 Cf. A006218, A051731, A116477. %K A143724 nonn,tabl %O A143724 1,3 %A A143724 _Gary W. Adamson_, Aug 29 2008 %E A143724 Diagonal sequence corrected to A116477 by _Georg Fischer_, Jun 27 2023