OFFSET
1,1
COMMENTS
Column 3 of A252192.
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..210
FORMULA
Empirical: a(n) = 7*a(n-3) -14*a(n-6) +8*a(n-9) for n>15.
EXAMPLE
Some solutions for n=4
..2..1..3..2..1....3..2..1..0..2....0..1..2..0..1....0..3..0..0..3
..1..2..0..1..2....2..0..1..2..0....0..3..3..0..0....0..2..1..3..2
..0..0..0..3..0....1..1..1..1..1....0..2..1..0..2....3..1..2..0..1
..2..1..3..2..1....3..2..1..3..2....3..1..2..0..1....0..0..3..0..3
..1..2..3..1..2....2..0..1..2..0....3..0..3..0..3....3..2..1..0..2
..3..3..0..0..0....1..1..1..1..1....0..2..1..0..2....3..1..2..3..2
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, Dec 15 2014
STATUS
approved