OFFSET
1,1
COMMENTS
Column 1 of A206010.
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..210
FORMULA
Empirical: a(n) = 8*a(n-2) + 4*a(n-3) for n>4.
Empirical g.f.: 2*x*(12 + 39*x + 18*x^2 + x^3) / (1 - 8*x^2 - 4*x^3). - Colin Barker, Jun 13 2018
EXAMPLE
Some solutions for n=4:
..2..1....1..1....2..1....1..0....2..0....2..1....2..1....1..0....0..1....2..0
..2..2....0..1....2..2....2..2....2..2....0..1....1..1....1..2....1..1....2..2
..2..0....1..1....1..2....1..2....0..2....1..1....1..2....2..2....1..2....2..0
..2..2....0..1....1..1....1..1....2..2....2..1....1..1....0..1....1..1....2..2
..1..2....1..1....1..0....0..1....1..2....1..1....1..2....1..1....0..1....0..1
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, Feb 02 2012
STATUS
approved