A259100 Triangle read by rows, arising in the enumeration of corners.

1, 0, 1, 0, 2, 1, 0, 3, 2, 1, 0, 4, 5, 2, 1, 0, 5, 8, 5, 2, 1, 0, 6, 14, 10, 5, 2, 1, 0, 7, 20, 18, 10, 5, 2, 1, 0, 8, 30, 30, 20, 10, 5, 2, 1

Offset: 0

Author

N. J. A. Sloane, Jun 22 2015

Keywords

• nonn
• tabl
• more

Examples

			Triangle begins:
  1;
  0,  1;
  0,  2,  1;
  0,  3,  2,  1;
  0,  4,  5,  2,  1;
  0,  5,  8,  5,  2,  1;
  0,  6, 14, 10,  5,  2,  1;
  0,  7, 20, 18, 10,  5,  2,  1;
  0,  8, 30, 30, 20, 10,  5,  2,  1;
  ...
		

Links

• G. Kreweras, Sur les extensions linéaires d'une famille particuliere d'ordres partiels, Discrete Math., 27 (1979), 279-295.
• G. Kreweras, Sur les extensions linéaires d'une famille particulière d'ordres partiels, Discrete Math., 27 (1979), 279-295. (Annotated scanned copy)

Crossrefs

Row sums = A006330.

Formula

Kreweras gives a recurrence on page 281.