A224117 Number of idempotent n X n 0..1 matrices of rank n-2.

0, 1, 27, 282, 2050, 12405, 67557, 344708, 1686132, 8017335, 37383775, 171917790, 782635542, 3535573769, 15875062665, 70921483080, 315457366696

Offset: 1

Author

R. H. Hardin Apr 09 2013

Keywords

• nonn

Comments

Column 1 of A224118

Examples

			Some solutions for n=3
..0..0..0....1..0..0....0..0..0....0..0..1....0..0..0....1..0..0....0..0..0
..1..1..0....0..0..0....0..1..0....0..0..1....0..0..0....1..0..0....1..0..1
..0..0..0....0..0..0....0..1..0....0..0..1....1..0..1....1..0..0....1..0..1