OFFSET
1,2
COMMENTS
Every 0 is next to 0 4's, every 1 is next to 1 3's, every 2 is next to 2 2's, every 3 is next to 3 1's, every 4 is next to 4 0's.
Diagonal of A197217.
EXAMPLE
Some solutions for n=4
..1..3..1..0....1..3..1..0....1..3..1..1....0..0..0..0....2..2..0..0
..1..1..0..0....0..1..1..0....0..1..1..3....0..1..2..2....2..2..0..0
..3..1..1..0....0..1..3..1....0..0..0..1....1..3..2..2....0..1..0..0
..1..1..3..1....0..0..0..0....0..0..0..0....0..1..0..0....1..3..1..0
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, Oct 11 2011
STATUS
approved