OFFSET
1,2
COMMENTS
Diagonal of A267338.
EXAMPLE
Some solutions for n=4
..0..1..1..2....0..1..2..3....0..0..1..2....0..1..2..3....0..1..2..3
..0..1..2..3....0..1..2..3....0..1..2..3....1..2..3..0....1..1..2..3
..1..2..3..0....0..1..2..3....0..1..2..3....2..3..0..1....1..2..3..0
..2..3..3..0....1..2..3..0....1..2..3..3....2..3..0..1....2..3..0..0
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jan 13 2016
STATUS
approved