OFFSET
1,3
COMMENTS
Diagonal of A280810.
EXAMPLE
Some solutions for n=4
..0..1..0..1. .0..0..1..0. .0..0..1..0. .0..1..1..0. .0..1..0..1
..0..1..1..1. .0..1..1..1. .1..1..0..1. .1..0..0..0. .0..0..0..1
..0..1..0..0. .0..0..0..1. .0..0..1..0. .0..1..0..1. .1..1..1..0
..0..0..1..1. .1..1..0..1. .1..1..1..0. .0..1..1..0. .0..0..0..0
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jan 08 2017
STATUS
approved