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A159936
Triangle read by rows, A051731 * A054533 * transpose(A101688), provided A101688 is read as a square array.
1
1, 1, 1, 1, 1, 2, 1, 1, 2, 2, 1, 1, 2, 3, 4, 1, 1, 2, 2, 3, 2, 1, 1, 2, 3, 4, 5, 6, 1, 1, 2, 2, 4, 4, 4, 4, 1, 1, 2, 3, 3, 3, 6, 6, 6, 1, 1, 2, 2, 4, 4, 5, 4, 5, 4, 1, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 1, 1, 2, 2, 3, 2, 4, 4, 6, 6, 4, 4, 1, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 1, 1, 2, 2, 4, 4, 6, 6, 7, 6, 7, 6, 7, 6
OFFSET
1,6
COMMENTS
Row sums = A057661: (1, 2, 4, 6, 11, 11, 22,...). Right border = A000010, phi(n).
FORMULA
Triangle read by rows, A051731 * A054533 * A000012. A051731 = the inverse Mobius transform. A054533 = the lower left half of the Ramanujan sum table. The operation (* transpose(A101688)) takes partial sums of (A051731 * A054533) starting from the right. [Edited by Petros Hadjicostas, Jul 30 2019]
EXAMPLE
First few rows of the triangle are as follows:
1;
1, 1;
1, 1, 2;
1, 1, 2, 2;
1, 1, 2, 3, 4;
1, 1, 2, 2, 3, 2;
1, 1, 2, 3, 4, 5, 6;
1, 1, 2, 2, 4, 4, 4, 4;
1, 1, 2, 3, 3, 3, 6, 6, 6;
1, 1, 2, 2, 4, 4, 5, 4, 5, 4;
1, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10;
1, 1, 2, 2, 3, 2, 4, 4, 6, 6, 4, 4;
1, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12;
1, 1, 2, 2, 4, 4, 6, 6, 7, 6, 7, 6, 7, 6;
1, 1, 2, 3, 3, 3, 5, 4, 3, 5, 9, 8, 10, 9, 8;
1, 1, 2, 2, 4, 4, 4, 4, 8, 8, 8, 8, 8, 8, 8, 8;
...
KEYWORD
nonn,tabl
AUTHOR
Gary W. Adamson, Apr 26 2009
EXTENSIONS
Name edited by Petros Hadjicostas, Jul 30 2019
STATUS
approved