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A127738
Triangle read by rows: the matrix product A004736 * A127701 of two triangular matrices.
0
1, 3, 2, 5, 5, 3, 7, 8, 7, 4, 9, 11, 11, 9, 5, 11, 14, 15, 14, 11, 6, 13, 17, 19, 19, 17, 13, 7, 15, 20, 23, 24, 23, 20, 15, 8, 17, 23, 27, 29, 29, 27, 23, 17, 9, 19, 26, 31, 34, 35, 34, 31, 26, 19, 10
OFFSET
1,2
COMMENTS
Left column = A028387: (1, 5, 11, 19, 29, 41, 55, ...).
FORMULA
T(n,k) = Sum_{j=k..n} A004736(n,j)*A127701(j,k). - R. J. Mathar, Aug 31 2022
T(n,k) = k+(k+1)*(n-k) = n+k*(n-k) = n +A094053(n,k) = A059036(n,k). - R. J. Mathar, Aug 31 2022
EXAMPLE
First few rows of the triangle:
1;
3, 2;
5, 5, 3;
7, 8, 7, 4;
9, 11, 11, 9, 5;
11, 14, 15, 14, 11, 6;
13, 17, 19, 19, 17, 13, 7;
...
CROSSREFS
Cf. A004736, A127701, A008778 (row sums), A028387.
Sequence in context: A094787 A132778 A182289 * A350900 A001598 A375920
KEYWORD
nonn,tabl,easy
AUTHOR
Gary W. Adamson, Jan 27 2007
STATUS
approved