OFFSET
1,2
EXAMPLE
Some solutions for n=2
..2..2..2..2....2..2..0..0....0..0..3..3....0..0..1..1....2..2..0..0
..2..1..1..2....2..2..0..0....0..0..3..3....0..0..1..1....2..2..0..0
..2..1..1..2....0..0..1..1....3..3..2..2....1..1..3..3....0..0..3..3
..2..2..2..2....0..0..1..1....3..3..2..2....1..1..3..3....0..0..3..3
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin Mar 31 2012
STATUS
approved