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A130162
Triangle read by rows: A051731 * A000837 as a diagonalized matrix.
2
1, 1, 1, 1, 0, 2, 1, 1, 0, 3, 1, 0, 0, 0, 6, 1, 1, 2, 0, 0, 7, 1, 0, 0, 0, 0, 0, 14, 1, 1, 0, 3, 0, 0, 0, 17, 1, 0, 2, 0, 0, 0, 0, 0, 27, 1, 1, 0, 0, 6, 0, 0, 0, 0, 34, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 55, 1, 1, 2, 3, 0, 7, 0, 0, 0, 0, 0, 63
OFFSET
1,6
COMMENTS
Right border = A000837 (offset 1).
Row sums = partition numbers A000041 starting (1, 2, 3, 5, 7, ...).
FORMULA
A051731 * A000837 (starting at offset 1) as a diagonalized matrix M, where M = T(n,k) = A000837(n) * 0^(n-k), 1<=k<=n; i.e., (1; 0,1; 0,0,2; 0,0,0,3; 0,0,0,0,6;...).
A051731 = inverse Moebius transform.
EXAMPLE
First few rows of the triangle:
1;
1, 1;
1, 0, 2;
1, 1, 0, 3;
1, 0, 0, 0, 6;
1, 1, 2, 0, 0, 7;
1, 0, 0, 0, 0, 0, 14;
1, 1, 0, 3, 0, 0, 0, 17;
...
MATHEMATICA
rows = 12; A000837[n_] := Sum[ MoebiusMu[n/d]*PartitionsP[d], {d, Divisors[n]}]; A000837diag = DiagonalMatrix[Array[A000837, rows]]; A051731 = Table[ If[Mod[n, k] == 0, 1, 0], {n, 1, rows}, {k, 1, rows}]; A130162 = A051731.A000837diag; Table[ A130162[[n, k]], {n, 1, rows}, {k, 1, n}] // Flatten (* Jean-François Alcover, Oct 03 2013 *)
CROSSREFS
KEYWORD
nonn,tabl
AUTHOR
Gary W. Adamson, May 13 2007
EXTENSIONS
More terms from Jean-François Alcover, Oct 03 2013
Offset changed to 1 by Georg Fischer, Jun 27 2023
STATUS
approved