A131782 Triangle read by rows: (A004736 * A000012) + (A000012 * A004736) - A000012 as infinite lower triangular matrices.

1, 5, 1, 11, 5, 1, 19, 11, 5, 1, 29, 19, 11, 5, 1, 41, 29, 19, 11, 5, 1, 55, 41, 29, 19, 11, 5, 1, 71, 55, 41, 29, 19, 11, 5, 1, 89, 71, 55, 41, 29, 19, 11, 5, 1, 109, 89, 71, 55, 41, 29, 19, 11, 5, 1, 131, 109, 89, 71, 55, 41, 29, 19, 11, 5, 1, 155, 131, 109, 89, 71, 55, 41, 29, 19, 11, 5, 1

Offset: 1

Author

Gary W. Adamson, Jul 14 2007

Keywords

• nonn
• tabl

Comments

Row sums = A084990 starting (1, 6, 17, 36, 65, 106, ...).

Examples

			First few rows of the triangle:
   1;
   5,  1;
  11,  5,  1;
  19, 11,  5,  1;
  29, 19, 11,  5,  1;
  41, 29, 19, 11,  5,  1;
  55, 41, 29, 19, 11,  5,  1;
  ...
		

Crossrefs

Cf. A004736, A028387, A084990.

Formula

n-th row = n descending terms of A028387: (1, 5, 11, 19, 29, 41, 55, ...). By columns, each column = A028387: (1, 5, 11, 19, 29, ...).

Extensions

Sign in definition and a(41) corrected; more terms from Georg Fischer, Jun 05 2023