OFFSET
1,1
COMMENTS
Column 1 of A184197.
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..200
FORMULA
Empirical: a(n) = 4*a(n-1) - 2*a(n-2) - 2*a(n-3).
Empirical g.f.: x*(2 + x)*(3 - 4*x) / (1 - 4*x + 2*x^2 + 2*x^3). - Colin Barker, Apr 12 2018
EXAMPLE
Some solutions for 3 X 2:
..1..1....1..0....0..1....0..1....0..1....1..1....0..1....1..0....1..0....0..1
..0..0....0..1....1..1....1..0....0..1....1..1....0..1....1..1....1..0....1..1
..0..0....0..1....0..1....0..1....1..1....0..1....1..0....0..0....0..1....1..1
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jan 10 2011
STATUS
approved