OFFSET
1,4
COMMENTS
Row 10 of A188147.
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..50
FORMULA
Empirical: a(n) = 16268*n^2 - 115548*n + 186528 for n>8.
Conjectures from Colin Barker, Apr 27 2018: (Start)
G.f.: 8*x^4*(462 + 1864*x + 1890*x^2 + 440*x^3 - 314*x^4 - 222*x^5 - 49*x^6 - 4*x^7) / (1 - x)^3.
a(n) = 3*a(n-1) - 3*a(n-2) + a(n-3) for n>11.
(End)
EXAMPLE
Some solutions for 4 X 4:
..0..8..9.10....0..7..8..9....0..3..4..5....0..0..6..7....1..0..0.10
..0..7..6..1....0..6..5.10....1..2..7..6....0..4..5..8....2..7..8..9
..0..0..5..2....0..3..4..0...10..9..8..0....0..3..2..9....3..6..0..0
..0..0..4..3....0..2..1..0....0..0..0..0....0..0..1.10....4..5..0..0
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, Mar 22 2011
STATUS
approved