OFFSET
1,1
COMMENTS
Diagonal of A227060
EXAMPLE
Some solutions for n=3
..1..0.-1....0..0..1....0..1..0....0..1.-2....1.-2..1....0..0..1....0..0..1
..0..0..0....1..0.-2....1.-1..0....0..0..1....0..1.-2....1..0.-1....0..1.-2
.-1..0.-1...-1..0..0...-1..0..0....0.-1..0....0..0..0...-1..0..0....0.-1..0
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin Jun 30 2013
STATUS
approved