OFFSET
1,1
COMMENTS
Column 1 of A235437.
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..210
FORMULA
Empirical: a(n) = 8*a(n-1) - a(n-2) - 64*a(n-3) - 14*a(n-4) + 88*a(n-5) + 8*a(n-6) - 24*a(n-7).
Empirical g.f.: x*(81 - 65*x - 596*x^2 - 38*x^3 + 800*x^4 + 48*x^5 - 216*x^6) / ((1 - x)*(1 - 2*x - 8*x^2 - 4*x^3)*(1 - 5*x - 8*x^2 + 6*x^3)). - Colin Barker, Mar 19 2018
EXAMPLE
Some solutions for n=5:
..1..0....1..1....0..1....1..0....0..0....1..1....0..0....0..2....1..0....0..2
..0..0....2..0....0..1....0..2....0..2....1..1....1..0....0..1....1..1....2..2
..0..1....1..1....2..0....2..1....1..0....0..0....0..2....0..2....2..0....0..1
..1..2....2..0....0..1....0..2....2..0....2..0....2..1....1..0....2..2....1..2
..0..1....2..2....0..2....0..1....0..1....1..1....2..0....1..2....0..1....0..2
..2..1....2..0....2..1....0..2....0..2....2..0....2..2....1..0....2..2....0..0
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jan 10 2014
STATUS
approved