A224114 T(n,k) = Number of idempotent n X n 0..k matrices of rank 2.

0, 0, 1, 0, 1, 21, 0, 1, 51, 282, 0, 1, 93, 1434, 3070, 0, 1, 147, 4182, 30410, 29505, 0, 1, 213, 9762, 136990, 546465, 260967, 0, 1, 291, 19110, 467290, 3784335, 8815317, 2175236, 0, 1, 381, 34602, 1240310, 18925485, 94529631

Offset: 1

Author

R. H. Hardin, Apr 09 2013

Keywords

• nonn
• tabl
• more

Comments

Table starts:

.......0.......0........0........0.......0.....0...0.0.0

.......1.......1........1........1.......1.....1...1.1

......21......51.......93......147.....213...291.381

.....282....1434.....4182.....9762...19110.34602

....3070...30410...136990...467290.1240310

...29505..546465..3784335.18925485

..260967.8815317.94529631

.2175236

Examples

			Some solutions for n=3, k=4:
..1..0..2....0..1..3....0..0..1....0..0..0....0..0..0....1..0..0....1..3..0
..0..1..3....0..1..0....0..1..0....3..1..0....0..1..0....0..1..1....0..0..0
..0..0..0....0..0..1....0..0..1....3..0..1....4..0..1....0..0..0....0..3..1
		

Crossrefs

Row 3 is A224334.