OFFSET
1,2
COMMENTS
Column 4 of A221873
EXAMPLE
Some solutions for n=3
..2..1..1..2....1..2..0..0....0..1..0..0....0..2..1..0....0..3..0..1
..1..1..0..1....0..3..0..3....2..3..1..1....0..3..1..1....0..4..3..0
..1..0..2..0....0..1..2..0....0..3..0..1....0..2..2..0....0..0..1..0
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin Jan 28 2013
STATUS
approved