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A128220
Triangle, A127701 * A000012.
1
1, 3, 2, 4, 4, 3, 5, 5, 5, 4, 6, 6, 6, 6, 5, 7, 7, 7, 7, 7, 6, 8, 8, 8, 8, 8, 8, 7, 9, 9, 9, 9, 9, 9, 9, 8, 10, 10, 10, 10, 10, 10, 10, 10, 9, 11, 11, 11, 11, 11, 11, 11, 11, 11, 10
OFFSET
1,2
COMMENTS
Row sums = A028387: (1, 5, 11, 19, 29, 41, 55, ...) A000012 * A127701 = A128219.
FORMULA
A127701 * A000012 as infinite lower triangular matrices. Triangle read by rows: a(1) = 1; n-th row = (n-1) terms of (n+1) followed by "n".
EXAMPLE
First few rows of the triangle:
1;
3, 2;
4, 4, 3;
5, 5, 5, 4;
6, 6, 6, 6, 5;
7, 7, 7, 7, 7, 6;
...
CROSSREFS
KEYWORD
nonn,tabl
AUTHOR
Gary W. Adamson, Feb 19 2007
STATUS
approved