OFFSET
1,2
COMMENTS
Row 4 of A188147.
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..50
FORMULA
Empirical: a(n) = 36*n^2 - 100*n + 56 for n>2.
Conjectures from Colin Barker, Apr 26 2018: (Start)
G.f.: 8*x^2*(1 + 7*x + 2*x^2 - x^3) / (1 - x)^3.
a(n) = 3*a(n-1) - 3*a(n-2) + a(n-3) for n>5.
(End)
EXAMPLE
Some solutions for 3 X 3:
..0..0..0....0..0..1....1..0..0....3..2..0....4..1..0....0..0..0....1..0..0
..0..2..1....0..3..2....2..0..0....4..1..0....3..2..0....4..0..0....2..3..4
..0..3..4....0..4..0....3..4..0....0..0..0....0..0..0....3..2..1....0..0..0
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, Mar 22 2011
STATUS
approved