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A127444
Triangle defined as the matrix product A051731*A127442, read by rows.
0
1, 2, -2, 2, -2, 0, 3, -4, 0, 1, 2, -2, 0, 1, -1, 4, -6, 0, 1, -1, 2, 2, -2, 0, 1, -1, 2, -2, 4, -6, 0, 2, -1, 2, -2, 1, 3, -4, 0, 1, -1, 2, -2, 1, 0, 4, -6, 0, 2, -2, 2, -2, 1, 0, 1, 2, -2, 0, 1, -1, 2, -2, 1, 0, 1, -2, 6, -10, 0, 3, -2, 4, -2, 1
OFFSET
1,2
COMMENTS
Row sums = 0.
FORMULA
T(n,k) = sum_{j=k..n} A051731(n,j)*A127442(j,k) = sum_{j=k..n, j|n} A127442(j,k), 1<=k<=n.
EXAMPLE
First few rows of the triangle are:
1;
2, -2;
2, -2, 0;
3, -4, 0, 1;
2, -2, 0, 1, -1;
4, -6, 0, 1, -1, 2;
2, -2, 0, 1, -1, 2, -2;
...
CROSSREFS
Cf. A000005 (column k=1), A051731, A127442.
Sequence in context: A214666 A320471 A333180 * A241477 A362485 A268243
KEYWORD
tabl,easy,sign
AUTHOR
Gary W. Adamson, Jan 14 2007
STATUS
approved