OFFSET
1,1
COMMENTS
Column 4 of A221609.
EXAMPLE
Some solutions for n=3
..1..2..1..0....0..2..2..1....1..1..0..2....0..2..2..1....0..3..2..0
..1..2..0..1....1..2..1..0....0..2..3..0....1..0..0..0....0..0..2..1
..1..1..2..0....1..1..1..0....1..0..1..1....1..3..2..0....0..2..2..0
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jan 20 2013
STATUS
approved