OFFSET
1,3
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..21
EXAMPLE
Some solutions for 4X4 with a(1,1)=0
..0..0..0..1....0..0..0..0....0..0..0..0....0..0..1..0....0..0..1..0
..0..1..0..1....0..1..1..0....0..1..0..0....0..0..0..0....0..0..0..1
..0..0..1..0....0..1..0..1....0..0..1..0....1..0..1..0....1..0..0..0
..1..1..0..1....0..0..1..0....0..0..0..1....0..0..0..1....0..1..0..1
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin Jun 28 2011
STATUS
approved