A251121 Number of (n+1)X(n+1) 0..1 arrays with no 2X2 subblock having the sum of its diagonal elements greater than the maximum of its antidiagonal elements.

10, 40, 108, 266, 580, 1214, 2420, 4702, 8926, 16680, 30766, 56180, 101734, 182956, 327080, 581742, 1030000, 1816290, 3191136, 5588050, 9755530, 16983260, 29489098

Offset: 1

Author

R. H. Hardin, Nov 30 2014

Keywords

• nonn

Comments

Diagonal of A251128

Examples

			Some solutions for n=4
..0..0..0..0..1....0..0..0..1..1....0..0..0..1..1....1..0..1..0..1
..0..0..0..0..1....0..0..0..0..0....1..0..0..0..0....1..0..1..0..1
..0..0..0..0..1....1..1..1..1..1....1..0..0..0..0....1..0..1..0..0
..0..0..0..0..0....0..0..0..0..0....1..0..0..0..0....1..0..1..0..0
..1..0..0..0..0....1..1..0..0..0....1..0..0..0..0....1..0..1..0..0