OFFSET
1,1
COMMENTS
Column 4 of A221337
EXAMPLE
Some solutions for n=3
..2..0..2..0....2..0..0..2....0..2..2..2....2..0..0..0....0..2..0..2
..2..0..0..0....0..0..0..2....2..0..0..0....2..0..2..2....0..2..2..0
..2..2..2..0....2..0..2..2....2..0..2..0....2..2..0..0....2..0..2..0
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin Jan 11 2013
STATUS
approved