OFFSET
1,1
COMMENTS
Column 3 of A189814.
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..200
FORMULA
Empirical: a(n) = 12*n^2 + 88*n - 240 for n>8.
Conjectures from Colin Barker, May 03 2018: (Start)
G.f.: 2*x*(14 + 5*x + x^2 - 2*x^3 + 2*x^4 - 7*x^5 + 3*x^6 - 4*x^7 + 2*x^9 - 2*x^10) / (1 - x)^3.
a(n) = 3*a(n-1) - 3*a(n-2) + a(n-3) for n>8.
(End)
EXAMPLE
Some solutions for n=3:
..3..1....2..2....0..0....2..1....2..0....3..3....1..1....1..1....3..2....1..1
..0..1....3..1....0..3....2..2....0..0....0..3....1..2....0..2....2..2....2..0
..3..2....3..3....2..0....4..1....2..3....3..0....4..1....3..3....3..3....3..3
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, Apr 28 2011
STATUS
approved