A124731 Triangle, row sums = powers of 3, companion to A124730.

1, 2, 1, 4, 3, 2, 8, 7, 10, 2, 16, 15, 34, 12, 4, 32, 31, 98, 46, 32, 4, 64, 63, 258, 144, 156, 36, 8, 128, 127, 642, 402, 600, 192, 88, 8, 256, 255, 1538, 1044, 2004, 792, 560, 96, 16

Offset: 0

Author

Gary W. Adamson & Roger L. Bagula, Nov 05 2006

Keywords

• nonn
• tabl

Comments

In A124730, the diagonals are switched. Row sums are powers of 3 in both triangles.

Examples

			Row 2 = (4, 3, 2) since (using the 3 X 3 matrix m = [2,0,0; 1,1,0; 0,2,2]), m^2 * [1,0,0] = [4,3,2].
First few rows of the triangle are:
1;
2, 1;
4, 3, 2;
8, 7, 10, 2;
16, 15, 34, 12, 4;
32, 31, 98, 46, 32, 4;
64, 63, 258, 144, 156, 36, 8;
...
		

Crossrefs

Cf. A124730, A124732.

Formula

Let M = the infinite bidiagonal matrix with (2,1,2,1...) in the main diagonal and (1,2,1,2...) in the subdiagonal. Extracting finite n X n matrices of this form, we take M^n * [1,0,0,0...].