OFFSET
1,3
COMMENTS
Diagonal of A216612
EXAMPLE
Some solutions for n=4
..x..0..x..1....x..0..x..1....x..0..x..1....x..0..x..1....x..0..x..1
..2..x..3..x....2..x..3..x....1..x..2..x....1..x..2..x....2..x..3..x
..x..4..x..1....x..4..x..1....x..3..x..4....x..0..x..3....x..4..x..1
..5..x..0..x....1..x..5..x....2..x..5..x....3..x..2..x....1..x..3..x
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin Sep 10 2012
STATUS
approved