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A130094
A051731 * an infinite lower triangular matrix with A007427 in the main diagonal.
0
1, 1, -2, 1, 0, -2, 1, -2, 0, 1, 1, 0, 0, 0, -2, 1, -2, -2, 0, 0, 4, 1, 0, 0, 0, 0, 0, -2, 1, -2, 0, 1, 0, 0, 0, 0, 1, 0, -2, 0, 0, 0, 0, 0, 1, 1, -2, 0, 0, -2, 0, 0, 0, 0, 4
OFFSET
1,3
COMMENTS
Right border = A007427. Row sums = mu(n), A008683. Nonzero terms by rows are substituted for the factors of n such that row sums = mu(n). Example: for row 6 we map (1, -2, -2, 0, 4), sum = 1, since the factors of 6 are 1, 2, 3 and 6.
FORMULA
Inverse Möbius transform of a triangular matrix with A007427 in the main diagonal and the rest zeros.
EXAMPLE
First few rows of the triangle are:
1;
1, -2;
1, 0, -2;
1, -2, 0, 1;
1, 0, 0, 0, -2;
1, -2, -2, 0, 0, 4;
1, 0, 0, 0, 0, 0, -2;
1, -2, 0, 1, 0, 0, 0, 0;
1, 0, -2, 0, 0, 0, 0, 0, 1;
...
CROSSREFS
KEYWORD
tabl,sign
AUTHOR
Gary W. Adamson, May 06 2007
STATUS
approved