OFFSET
1,1
COMMENTS
Column 4 of A206238.
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..210
FORMULA
Empirical: a(n) = a(n-1) + 339*a(n-3) - 339*a(n-4) for n>8.
Empirical g.f.: 8*x*(205 + 511*x + 2680*x^2 - 37425*x^3 - 54141*x^4 + 67251*x^5 - 86751*x^6 + 107163*x^7) / ((1 - x)*(1 - 339*x^3)). - Colin Barker, Jun 14 2018
EXAMPLE
Some solutions for n=4:
..0..0..1..1..2....0..0..1..2..0....0..0..1..1..2....0..1..0..0..2
..1..1..2..1..1....0..3..2..2..0....1..1..2..1..1....2..0..0..3..0
..2..1..1..2..1....3..2..2..0..1....3..1..1..2..1....0..0..1..0..0
..3..0..1..1..2....2..2..3..1..1....1..2..1..1..2....3..3..0..0..3
..3..3..2..1..2....2..3..1..1..0....1..1..2..1..1....1..3..0..1..2
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, Feb 05 2012
STATUS
approved