OFFSET
1,1
COMMENTS
Column 2 of A209796.
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..210
FORMULA
Empirical: a(n) = 14*a(n-1) + 27*a(n-2) - 64*a(n-3) + 22*a(n-4).
Empirical g.f.: 3*x*(68 + 105*x - 282*x^2 + 99*x^3) / (1 - 14*x - 27*x^2 + 64*x^3 - 22*x^4). - Colin Barker, Jul 13 2018
EXAMPLE
Some solutions for n=4.
..1..1..1....2..0..1....1..2..0....0..0..2....0..0..2....2..0..2....2..0..1
..1..0..0....0..0..0....0..2..0....0..1..1....0..1..1....2..2..2....2..0..2
..1..2..2....2..2..1....2..2..1....0..1..2....1..1..0....0..2..1....1..0..2
..0..0..0....2..0..0....2..0..1....0..0..2....1..2..2....2..2..1....1..2..2
..2..0..2....2..0..1....0..0..2....0..2..2....0..0..1....2..0..0....2..2..1
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, Mar 13 2012
STATUS
approved