OFFSET
1,1
COMMENTS
Column 6 of A215959
EXAMPLE
Some solutions for n=4
..0..x..1..x..2..x....0..x..1..x..2..x....0..x..1..x..2..x....0..x..1..x..0..x
..x..1..x..3..x..0....x..1..x..3..x..4....x..3..x..4..x..0....x..2..x..0..x..3
..3..x..2..x..0..x....1..x..0..x..5..x....1..x..5..x..0..x....1..x..0..x..4..x
..x..4..x..5..x..6....x..5..x..1..x..3....x..0..x..3..x..6....x..3..x..5..x..6
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin Aug 28 2012
STATUS
approved