OFFSET
1,1
COMMENTS
Column 7 of A204284.
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..210
FORMULA
Empirical: a(n) = 3*a(n-1) -6*a(n-4) +4*a(n-6) for n>8.
Empirical g.f.: x*(29731 - 87310*x - 3659*x^2 - 4056*x^3 + 174812*x^4 + 7654*x^5 - 111900*x^6 - 256*x^7) / ((1 - x)*(1 - 2*x - 2*x^2)*(1 - 2*x^3)). - Colin Barker, Jun 06 2018
EXAMPLE
Some solutions for n=4:
..0..1..0..2..1..2..2..1..1....0..0..0..0..0..0..0..0..0
..0..1..0..2..1..2..2..1..1....0..0..0..0..0..0..0..0..0
..0..1..0..2..1..2..2..1..1....1..1..1..1..1..1..1..1..1
..0..1..0..2..1..2..2..1..1....1..1..1..1..1..1..1..1..1
..0..1..0..2..1..2..2..1..1....2..2..2..2..2..2..2..2..2
..0..1..0..2..1..2..2..1..1....1..1..1..1..1..1..1..1..1
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jan 13 2012
STATUS
approved