OFFSET
1,2
EXAMPLE
Some solutions for 4X4
..1..2..1..2....1..2..2..1....1..2..0..0....1..1..1..1....1..2..1..1
..2..2..1..2....2..2..1..2....2..2..1..0....1..1..1..1....2..2..1..1
..1..1..1..2....2..1..1..2....0..1..2..2....1..1..1..0....1..1..1..1
..2..2..2..1....1..2..2..1....0..0..2..1....1..1..0..0....1..1..1..1
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin Jul 27 2011
STATUS
approved