OFFSET
1,1
COMMENTS
Column 2 of A185477
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..200
FORMULA
Empirical: a(n) = (1/9979200)*n^11
+ (29/3628800)*n^10
+ (257/241920)*n^9
+ (4621/120960)*n^8
+ (400927/604800)*n^7
+ (1134257/172800)*n^6
+ (31386443/725760)*n^5
+ (20355493/90720)*n^4
+ (80111509/100800)*n^3
+ (40459121/25200)*n^2
+ (7603747/4620)*n
+ 273
EXAMPLE
Some solutions for 6X4
..0..0..0..0....0..0..0..0....0..0..0..1....0..0..0..0....0..0..0..0
..0..0..0..1....0..0..0..1....0..0..0..1....0..0..0..2....0..0..0..1
..0..0..1..1....0..0..1..2....0..0..0..2....0..0..1..1....0..0..0..1
..0..0..1..2....0..0..1..2....0..0..1..2....1..1..2..2....0..0..1..1
..0..0..1..2....0..1..1..1....0..1..2..1....1..2..1..2....0..1..0..1
..0..0..2..1....1..1..2..1....1..2..2..1....1..2..2..0....2..2..2..1
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin Jan 28 2011
STATUS
approved