login
A227591
Number of nX3 0,1 arrays indicating 2X2 subblocks of some larger (n+1)X4 binary array having nonzero determinant
1
8, 64, 496, 3840, 29676, 229140, 1768536, 13647884, 105314460, 812639152, 6270496476, 48384225732, 373340106040, 2880746583772, 22228250112412, 171516305172416, 1323443833732092, 10211877627158916, 78796274109927720
OFFSET
1,1
COMMENTS
Column 3 of A227594
LINKS
FORMULA
Empirical: a(n) = 7*a(n-1) +7*a(n-2) +4*a(n-3) -69*a(n-4) -305*a(n-5) -518*a(n-6) -607*a(n-7) -271*a(n-8) -252*a(n-9) -12*a(n-10) +28*a(n-11)
EXAMPLE
Some solutions for n=4
..0..1..1....1..1..0....0..0..1....1..1..1....0..1..0....0..1..0....1..1..0
..0..0..0....0..1..1....1..0..1....1..1..0....1..0..1....1..0..0....1..1..1
..1..0..1....1..1..1....0..0..1....0..0..0....0..1..1....1..1..0....0..0..0
..1..0..0....0..0..0....0..1..1....1..1..1....0..1..1....1..0..0....1..1..1
CROSSREFS
Sequence in context: A122093 A267231 A267470 * A268943 A269639 A269536
KEYWORD
nonn
AUTHOR
R. H. Hardin Jul 17 2013
STATUS
approved