A131227 2*A051340 - A128174.

1, 2, 3, 1, 2, 5, 2, 1, 2, 7, 1, 2, 1, 2, 9, 2, 1, 2, 1, 2, 11, 1, 2, 1, 2, 1, 2, 13, 2, 1, 2, 1, 2, 1, 2, 15, 1, 2, 1, 2, 1, 2, 1, 2, 17, 2, 1, 2, 1, 2, 1, 2, 1, 2, 19

Offset: 0

Author

Gary W. Adamson, Jun 20 2007

Keywords

• nonn
• tabl

Comments

Row sums = A047383, numbers congruent to {1,5} mod 7: (1, 5, 8, 12, 15, 19, ...)

Examples

			First few rows of the triangle:
  1;
  2, 3;
  1, 2, 5;
  2, 1, 2, 7;
  1, 2, 1, 2, 9;
  2, 1, 2, 1, 2, 11;
  1, 2, 1, 2, 1,  2, 13;
  ...
		

Crossrefs

Cf. A051340, A128174, A047383, A131228, A131229.

Formula

2*A051340 - A128174 as infinite lower triangular matrices.