OFFSET
1,1
COMMENTS
Column 4 of A203826.
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..210
FORMULA
Empirical: a(n) = 117*a(n-1) -34398*a(n-3) +86436*a(n-4).
Empirical g.f.: 11664*x*(9 - 24*x - 2744*x^2 + 7056*x^3) / ((1 - 117*x + 294*x^2)*(1 - 294*x^2)). - Colin Barker, Jun 05 2018
EXAMPLE
Some solutions for n=4:
..0..1..0..3..3....1..0..0..0..0....1..2..0..1..0....3..3..3..2..1
..2..2..2..1..1....3..2..2..1..1....0..2..3..1..2....0..1..0..2..0
..3..0..3..3..2....1..0..3..3..2....1..2..0..0..2....3..2..3..3..3
..1..0..1..1..0....1..0..1..0..0....0..3..3..3..2....0..0..0..0..1
..2..2..2..2..3....1..0..1..2..1....0..1..1..0..2....2..3..2..2..2
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jan 06 2012
STATUS
approved