OFFSET
1,1
COMMENTS
Column 1 of A186472.
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..200
FORMULA
Empirical: a(n) = 2*a(n-1) + a(n-2) - 4*a(n-3) + 4*a(n-4) - 2*a(n-5) for n>10.
Empirical g.f.: x*(81 - 79*x + 30*x^2 + 54*x^3 - 37*x^4 - 40*x^5 - 4*x^6 + 26*x^7 - 2*x^8 + x^9) / ((1 - x)*(1 - x - 2*x^2 + 2*x^3 - 2*x^4)). - Colin Barker, Feb 28 2018
EXAMPLE
Some solutions for 3 X 2:
..1..1....1..0....1..0....0..1....1..2....0..0....2..2....1..2....0..0....2..0
..0..0....1..0....0..0....2..0....0..0....1..0....2..0....1..0....1..0....0..2
..0..0....0..1....0..2....0..2....0..0....2..1....0..2....0..1....1..1....1..1
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, Feb 22 2011
STATUS
approved