login
A224115
Number of idempotent 4X4 0..n matrices of rank 2.
1
282, 1434, 4182, 9762, 19110, 34602, 56982, 89766, 134298, 194262, 271074, 371478, 494346, 647358, 833226, 1057542, 1321482, 1636314, 1999926, 2425794, 2913678, 3472242, 4104942, 4828626
OFFSET
1,1
EXAMPLE
Some solutions for n=3
..0..0..0..0....1..0..0..0....0..0..0..0....0..0..0..0....1..0..0..0
..1..1..0..0....0..1..1..0....1..1..0..0....1..1..0..0....0..1..0..0
..2..1..0..1....0..0..0..0....0..0..1..0....1..1..0..1....2..2..0..0
..1..0..0..1....0..3..3..0....0..0..1..0....0..0..0..1....0..3..0..0
CROSSREFS
Row 4 of A224114.
Sequence in context: A250580 A252364 A345704 * A248459 A172627 A172725
KEYWORD
nonn,more
AUTHOR
R. H. Hardin, Apr 09 2013
STATUS
approved