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A125026
Triangle read by rows: T(n,k) = k*binomial(n,k) + binomial(n-1,k) (1 <= k <= n).
3
1, 3, 2, 5, 7, 3, 7, 15, 13, 4, 9, 26, 34, 21, 5, 11, 40, 70, 65, 31, 6, 13, 57, 125, 155, 111, 43, 7, 15, 77, 203, 315, 301, 175, 57, 8, 17, 100, 308, 574, 686, 532, 260, 73, 9, 19, 126, 444, 966, 1386, 1344, 876, 369, 91, 10, 21, 155, 615, 1530, 2562, 2982, 2430, 1365
OFFSET
1,2
COMMENTS
Also A007318 * A127899 (unsigned) as a product of two infinite lower triangular matrices. - Gary W. Adamson, Feb 19 2007
EXAMPLE
First few rows of the triangle are
1;
3, 2;
5, 7, 3;
7, 15, 13, 4;
9, 26, 34, 21, 5;
11, 40, 70, 65, 31, 6;
13, 57, 125, 155, 111, 43, 7;
...
MAPLE
T:=(n, k)->k*binomial(n, k)+binomial(n-1, k): for n from 1 to 12 do seq(T(n, k), k=1..n) od; # yields sequence in triangular form
CROSSREFS
Cf. A099035 (row sums).
Sequence in context: A181883 A021311 A128224 * A130295 A208613 A209584
KEYWORD
nonn,tabl
AUTHOR
Gary W. Adamson, Nov 15 2006
EXTENSIONS
Edited by N. J. A. Sloane, Nov 29 2006
STATUS
approved