OFFSET
1,1
COMMENTS
Column 2 of A229847.
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..210
FORMULA
Empirical: a(n) = 5*a(n-1) + 2*a(n-2) - a(n-3) - 5*a(n-4).
Empirical g.f.: 3*x*(1 - 3*x^3) / ((1 - x)*(1 - 4*x - 6*x^2 - 5*x^3)). - Colin Barker, Mar 17 2018
EXAMPLE
Some solutions for n=3:
..0..2....2..1....2..0....0..2....0..2....2..0....1..1....1..1....2..0....0..1
..2..0....0..1....0..0....1..1....2..1....2..0....0..1....2..2....1..1....2..1
..0..2....2..1....2..2....2..0....0..1....1..1....2..1....0..0....0..2....1..1
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, Oct 01 2013
STATUS
approved