OFFSET
1,1
COMMENTS
Row 8 of A188553.
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..200
FORMULA
Empirical: a(n) = (1/40320)*n^8 - (1/2016)*n^7 + (19/2880)*n^6 - (7/180)*n^5 + (1247/5760)*n^4 - (85/288)*n^3 + (17911/10080)*n^2 + (1961/840)*n + 5.
Conjectures from Colin Barker, Apr 28 2018: (Start)
G.f.: x*(9 - 64*x + 203*x^2 - 372*x^3 + 430*x^4 - 320*x^5 + 150*x^6 - 40*x^7 + 5*x^8) / (1 - x)^9.
a(n) = 9*a(n-1) - 36*a(n-2) + 84*a(n-3) - 126*a(n-4) + 126*a(n-5) - 84*a(n-6) + 36*a(n-7) - 9*a(n-8) + a(n-9) for n>9.
(End)
EXAMPLE
Some solutions for 8 X 3:
..1..1..1....1..1..1....1..1..1....1..1..1....1..1..1....1..1..1....1..1..1
..1..1..1....1..1..0....1..1..1....1..1..1....1..1..1....1..1..1....1..1..1
..1..1..1....1..0..0....1..1..1....1..1..1....1..1..1....1..1..1....1..1..1
..1..1..1....0..0..0....1..1..1....1..1..1....1..1..1....1..1..0....1..1..1
..1..1..1....0..0..0....1..1..1....1..1..1....1..1..1....1..0..0....1..1..0
..1..1..0....0..0..0....1..1..1....1..0..0....1..1..1....0..0..0....1..0..0
..0..0..0....0..0..0....1..1..1....0..0..0....1..1..0....0..0..0....0..0..0
..0..0..0....0..0..0....1..0..0....0..0..0....0..0..0....0..0..0....0..0..0
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, Apr 04 2011
STATUS
approved