OFFSET
1,1
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..210
FORMULA
Empirical: a(n) = 3*a(n-3) + 10*a(n-4) - 12*a(n-7) - 6*a(n-8) for n>12.
Empirical g.f.: 2*x*(147 + 361*x + 686*x^2 + 889*x^3 - 36*x^4 - 792*x^5 - 1616*x^6 - 1190*x^7 - 622*x^8 - 327*x^9 - 62*x^10 + 5*x^11) / (1 - 3*x^3 - 10*x^4 + 12*x^7 + 6*x^8). - Colin Barker, Oct 20 2018
EXAMPLE
Some solutions for n=5:
..0..2..1....1..0..0....1..0..0....2..0..1....1..2..2....2..2..1....1..2..1
..2..1..0....2..1..0....1..0..1....1..2..0....0..0..2....0..0..0....2..1..0
..0..0..0....1..2..0....0..0..2....0..1..2....1..0..1....2..1..0....0..0..0
..0..1..2....0..0..0....2..1..2....0..0..0....2..0..0....1..2..1....0..1..2
..1..2..1....0..2..1....2..0..0....2..1..0....2..1..2....0..0..2....0..2..1
..2..1..0....1..0..2....1..1..0....2..1..0....1..0..2....0..1..0....2..1..0
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jan 17 2014
STATUS
approved