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A128090
Denominators in inverse of A128077, numerators = 1.
1
1, -4, 4, -18, -18, 9, -48, -48, -48, 16, -100, -100, -100, -100, 25, -180, -180, -180, -180, -180, 36, -294, -294, -294, -294, -294, -294, 49
OFFSET
1,2
COMMENTS
Row sums of the inverse of A128077: (1/1; -1/4, 1/4; -1/18, -1/18, 1/9; ...) = (1, 0, 0, 0, ...).
Row sums of unsigned terms: (1; 4, 4; 18, 18, 9; ...) = A128091.
A045991 = (0, 0, 4, 18, 48, 100, ...).
FORMULA
Denominators in inverse triangular matrix of A128077, i.e., inverse of (1; 1, 4; 1, 2, 9; 1, 2, 3, 16; ...).
EXAMPLE
First few rows of the triangle:
1
-4, 4;
-18, -18, 9;
-48, -48, -48, 16;
-100, -100, -100, -100, 25;
...
CROSSREFS
KEYWORD
tabl,frac,sign,more
AUTHOR
Gary W. Adamson, Feb 14 2007
STATUS
approved