OFFSET
1,2
COMMENTS
Diagonal of A275504.
EXAMPLE
Some solutions for n=4
..0..0..0..1. .0..1..2..2. .0..0..0..0. .0..1..2..2. .0..1..2..1
..2..1..1..1. .0..2..2..0. .0..1..1..1. .1..1..2..0. .0..1..2..0
..2..1..2..2. .2..2..0..1. .1..1..2..2. .1..2..0..0. .1..2..0..0
..0..0..0..0. .2..1..0..1. .2..2..2..0. .2..0..0..1. .1..2..0..1
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jul 30 2016
STATUS
approved