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 A130540 #23 Apr 19 2020 12:46:26 %S A130540 1,3,1,4,0,1,7,3,0,1,6,0,0,0,1,12,4,3,0,0,1,8,0,0,0,0,0,1,15,7,0,3,0, %T A130540 0,0,1,13,0,4,0,0,0,0,0,1,18,6,0,0,3,0,0,0,0,1,12,0,0,0,0,0,0,0,0,0,1, %U A130540 28,12,7,4,0,3,0,0,0,0,0,1,14,0,0,0,0,0,0,0,0,0,0,0,1,24,8,0,0,0,0,3,0,0,0,0,0,0,1 %N A130540 Triangle read by rows T(n,k) in which column k lists the terms of A000203 interspersed with (k-1) zeros, 1 <= k <= n. %C A130540 The original definition was: A127093 * A125093^(-1). %C A130540 Left border = A000203, sigma(n): (1, 3, 4, 7, 6, ...). Row sums = A007429: (1, 4, 5, 11, 7, 20, 9, ...); = inverse Moebius transform applied to sigma(n); (i.e., inverse Moebius transform applied twice to natural numbers). %C A130540 T(n,k) is the total number of parts congruent to 0 mod k in the partitions of n into equal parts. - _Omar E. Pol_, Nov 19 2019 %C A130540 From _Omar E. Pol_, Jan 01 2020: (Start) %C A130540 Conjecture 1: the sum of odd-indexed terms in row n equals A327096(n). %C A130540 Conjecture 2: the sum of even-indexed terms in row n equals the n-th term of the sequence formed by A000004 and A007429 interleaved. %C A130540 Conjecture 3: alternating row sums give A288417. (End) %F A130540 A127093 * A125093^(-1), as infinite lower triangular matrices. %e A130540 First few rows of the triangle are: %e A130540 1; %e A130540 3, 1; %e A130540 4, 0, 1; %e A130540 7, 3, 0, 1; %e A130540 6, 0, 0, 0, 1; %e A130540 12, 4, 3, 0, 0, 1; %e A130540 8, 0, 0, 0, 0, 0, 1; %e A130540 15, 7, 0, 3, 0, 0, 0, 1; %e A130540 13, 0, 4, 0, 0, 0, 0, 0, 1; %e A130540 18, 6, 0, 0, 3, 0, 0, 0, 0, 1; %e A130540 12, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1; %e A130540 28, 12, 7, 4, 0, 3, 0, 0, 0, 0, 0, 1; %e A130540 14, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1; %e A130540 24, 8, 0, 0, 0, 0, 3, 0, 0, 0, 0, 0, 0, 1; %e A130540 24, 0, 6, 0, 4, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1; %e A130540 31, 15, 0, 7, 0, 0, 0, 3, 0, 0, 0, 0, 0, 0, 0, 1; %e A130540 ... %e A130540 Extended by _Omar E. Pol_, Nov 19 2019 %Y A130540 Cf. A000203, A007429, A127093, A125093, A244051, A288417, A327096. %K A130540 nonn,tabl %O A130540 1,2 %A A130540 _Gary W. Adamson_, Jun 03 2007 %E A130540 New name and more terms from _Omar E. Pol_, Nov 19 2019