|
%I #4 Dec 18 2015 18:18:33
%S 0,1,27,282,2050,12405,67557,344708,1686132,8017335,37383775,
%T 171917790,782635542,3535573769,15875062665,70921483080,315457366696
%N Number of idempotent n X n 0..1 matrices of rank n-2
%C Column 1 of A224118
%e Some solutions for n=3
%e ..0..0..0....1..0..0....0..0..0....0..0..1....0..0..0....1..0..0....0..0..0
%e ..1..1..0....0..0..0....0..1..0....0..0..1....0..0..0....1..0..0....1..0..1
%e ..0..0..0....0..0..0....0..1..0....0..0..1....1..0..1....1..0..0....1..0..1
%K nonn
%O 1,3
%A _R. H. Hardin_ Apr 09 2013
| 