OFFSET
1,1
COMMENTS
Diagonal of A206137.
EXAMPLE
Some solutions for n=4:
..1..2..3..1..2....0..1..2..1..2....2..1..2..3..0....3..1..3..2..3
..2..3..1..2..0....1..2..0..2..1....0..2..0..1..2....0..2..0..3..2
..1..2..3..0..2....0..1..2..1..3....1..3..2..3..0....1..3..1..0..3
..0..1..2..3..0....2..3..0..2..0....3..2..0..1..2....2..0..2..1..0
..3..0..1..2..3....1..2..3..1..2....1..3..1..2..1....3..1..3..2..1
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, Feb 04 2012
STATUS
approved