OFFSET
1,1
COMMENTS
Column 1 of A198642.
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..200
FORMULA
Empirical: a(n) = 12*a(n-1) -16*a(n-2) for n>3.
Conjectures from Colin Barker, May 15 2018: (Start)
G.f.: 4*x*(1 - x)*(1 - 2*x) / (1 - 12*x + 16*x^2).
a(n) = ((6 - 2*sqrt(5))^n*(-5+3*sqrt(5)) + (2*(3+sqrt(5)))^n*(5+3*sqrt(5))) / (16*sqrt(5)) for n>1.
(End)
EXAMPLE
Some solutions for n=3:
..0..1....0..1....0..1....0..1....0..1....0..1....0..1....0..1....0..1....0..1
..1..0....1..2....1..0....1..2....2..0....2..0....1..0....2..0....1..2....2..0
..0..2....2..0....2..1....0..1....0..1....0..1....2..1....1..2....0..1....1..2
..2..0....0..2....0..2....2..2....1..2....1..2....1..2....2..1....1..2....0..1
..1..1....2..0....2..0....2..2....2..0....2..1....0..1....0..2....2..1....1..0
..1..1....1..2....0..2....1..0....0..1....1..2....2..0....2..0....0..2....0..2
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, Oct 27 2011
STATUS
approved