OFFSET
1,1
COMMENTS
Column 2 of A186482.
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..200
FORMULA
Empirical: a(n) = 2*a(n-1) + 2*a(n-2) - 6*a(n-3) + 6*a(n-4) - 3*a(n-5) for n>13.
Empirical g.f.: x*(205 - 48*x - 433*x^2 + 1153*x^3 - 1116*x^4 - 110*x^5 + 336*x^6 + 112*x^7- 33*x^8 + 3*x^9 + x^10 + 2*x^12) / ((1 - x)*(1 - x - 3*x^2 + 3*x^3 - 3*x^4)). - Colin Barker, Apr 18 2018
EXAMPLE
Some solutions for 5 X 3:
..2..0..2....2..1..0....0..0..3....1..2..0....3..1..0....0..2..1....0..3..0
..0..2..0....2..0..1....0..0..0....1..0..2....0..0..1....0..0..2....2..0..3
..1..0..2....0..2..0....0..0..0....0..1..0....0..0..0....0..0..0....0..2..0
..0..1..0....3..0..2....2..0..0....0..0..1....3..0..0....3..0..0....0..0..2
..0..0..1....0..3..0....0..2..2....0..0..1....2..3..0....0..3..1....0..0..0
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, Feb 22 2011
STATUS
approved