A278771 Number of n X n 0..1 arrays with rows in nondecreasing lexicographic order and columns in nonincreasing lexicographic order, but with exactly two mistakes.

0, 2, 266, 19750, 1673658, 251740932, 90752836672, 93037538287080, 293564184229043556, 2953569640505846392444

Offset: 1

Author

R. H. Hardin, Nov 28 2016

Keywords

• nonn

Comments

Diagonal of A278778.

Examples

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

Crossrefs

Cf. A278778.