OFFSET
1,3
COMMENTS
Column 4 of A271194.
EXAMPLE
Some solutions for n=4
.....0........0........0........0........0........0........0........0
....1.0......1.0......1.1......1.1......1.2......1.2......1.0......1.2
...1.1.0....2.1.2....2.3.1....0.2.1....1.3.2....3.1.1....2.1.0....1.2.3
..2.1.3.2..1.2.2.0..2.0.3.1..0.3.2.2..4.4.3.2..3.3.1.1..1.2.2.1..0.0.2.2
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, Apr 01 2016
STATUS
approved