OFFSET
1,1
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..210
FORMULA
Empirical: a(n) = a(n-1) + 12*a(n-2) + 5*a(n-3) - 12*a(n-4) - 2*a(n-5).
Empirical g.f.: x*(4 + 9*x + 3*x^2 - 10*x^3 - 3*x^4) / (1 - x - 12*x^2 - 5*x^3 + 12*x^4 + 2*x^5). - Colin Barker, Jan 09 2019
EXAMPLE
Some solutions for n=4:
..0..0..1....0..0..0....0..0..0....1..0..0....1..0..0....0..0..0....1..0..0
..1..1..2....1..2..0....1..2..1....0..2..1....1..1..1....0..2..1....0..0..0
..0..1..1....1..0..0....0..0..0....1..0..1....1..0..0....1..0..0....1..2..1
..1..0..0....0..0..1....0..0..0....1..1..0....0..0..0....0..0..1....0..0..1
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, Dec 21 2015
STATUS
approved