OFFSET
1,1
COMMENTS
Column 2 of A222996.
A353047 is probably equal to 12 times this sequence. - N. J. A. Sloane, Jun 17 2022
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..33
FORMULA
Empirical: a(n) = 9*a(n-1) - 31*a(n-2) + 51*a(n-3) - 40*a(n-4) + 12*a(n-5).
Conjectures from Colin Barker, Feb 19 2018: (Start)
G.f.: x*(9 - 31*x + 51*x^2 - 40*x^3 + 12*x^4) / ((1 - x)^2*(1 - 2*x)^2*(1 - 3*x)).
a(n) = (-13 - 2^(6+n) + 3^(4+n) - 2*(1+2^(4+n))*n) / 4.
(End)
EXAMPLE
Some solutions for n=3:
..2..0....1..1....2..0....1..0....0..1....1..0....2..2....0..0....1..1....1..0
..0..0....1..1....1..1....2..2....0..1....2..2....1..1....1..2....0..0....2..2
..0..1....1..2....2..2....0..1....1..2....0..2....0..1....0..2....1..1....1..1
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, Mar 11 2013
STATUS
approved