A125026 Triangle read by rows: T(n,k) = k*binomial(n,k) + binomial(n-1,k) (1 <= k <= n).
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
Examples
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; ...
Crossrefs
Cf. A099035 (row sums).
Programs
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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
Extensions
Edited by N. J. A. Sloane, Nov 29 2006
Comments