OFFSET
1,1
COMMENTS
Column 1 of A198452.
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..200
FORMULA
Empirical: a(n) = 10*a(n-1) -25*a(n-2) +16*a(n-3).
Conjectures from Colin Barker, May 14 2018: (Start)
G.f.: x*(3 - 17*x + 16*x^2) / ((1 - x)*(1 - 9*x + 16*x^2)).
a(n) = 1/4 + (2^(-3-n)*((9+sqrt(17))^n*(-5+3*sqrt(17)) + (9-sqrt(17))^n*(5+3*sqrt(17)))) / sqrt(17).
(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....2..0....1..2....2..2....2..0....2..2....2..0....2..2....2..0
..1..0....1..2....2..0....1..2....1..1....2..0....1..1....2..0....1..1....2..0
..2..2....2..0....0..2....2..1....0..2....1..1....2..2....0..1....2..2....1..2
..1..1....2..0....0..2....2..1....0..2....2..2....1..1....0..1....0..0....1..2
..2..0....0..2....2..1....0..2....1..0....1..0....2..0....2..0....1..2....0..1
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, Oct 25 2011
STATUS
approved