A131948 Triangle T(n,k) = 2*A002024(n+1,k+1) + A007318(n,k) - 2, read by rows.

1, 3, 3, 5, 6, 5, 7, 9, 9, 7, 9, 12, 14, 12, 9, 11, 15, 20, 20, 15, 11, 13, 18, 27, 32, 27, 18, 13, 15, 21, 35, 49, 49, 35, 21, 15, 17, 24, 44, 72, 86, 72, 44, 24, 17, 19, 27, 54, 102, 144, 144, 102, 54, 27, 19

Offset: 0

Author

Gary W. Adamson, Jul 30 2007

Keywords

• nonn
• tabl

Comments

Row sums = A131949.

Examples

			First few rows of the triangle are:
1;
3, 3;
5, 6, 5;
7, 9, 9, 7;
9, 12, 14, 12, 9;
11, 15, 20, 20, 15, 11;
13, 18, 27, 32, 27, 18, 13;
15, 21, 35, 49, 49, 35, 21, 15;
...
		

Crossrefs

Cf. A002024, A007318, A131949.

Formula

2*A002024 + A007318 - 2*A000012 as infinite lower triangular matrices.