OFFSET
1,1
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..210
FORMULA
Empirical: a(n) = 2*a(n-1) - a(n-5) + a(n-6) - 2*a(n-7) + a(n-8) for n>10.
Empirical g.f.: 9*x*(76 - 70*x - 31*x^2 - 48*x^3 - 38*x^4 + 35*x^5 - 86*x^6 + 95*x^7 - 20*x^8 - 2*x^9) / ((1 - x)*(1 + x + x^2)*(1 - 2*x + x^3 - 2*x^4 + x^5)). - Colin Barker, Dec 07 2018
EXAMPLE
Some solutions for n=4:
..0..1..1..2..2....0..1..0..0..2....0..1..1..0..0....0..1..0..1..0
..2..1..2..1..2....2..0..0..1..1....0..1..0..1..1....1..2..2..1..1
..0..0..1..1..0....2..1..2..1..1....2..2..1..1..0....0..2..0..2..0
..2..0..2..0..2....1..1..2..2..0....2..2..0..0..1....1..1..2..2..0
..0..2..2..0..0....2..2..1..1..0....1..0..1..0..0....0..1..0..0..2
..0..2..0..2..0....1..2..1..2..1....2..0..0..1..1....1..2..2..0..0
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, Dec 23 2014
STATUS
approved