OFFSET
1,3
EXAMPLE
Some solutions for n=4
.....0........0........0........0........0........0........0........0
....1.2......1.2......1.2......1.2......1.2......1.2......1.2......1.2
...2.0.3....3.4.0....2.0.1....0.3.4....3.4.0....3.4.0....3.4.5....3.4.0
..3.1.4.1..4.2.5.4..3.1.3.0..4.5.2.5..0.5.3.6..4.5.3.6..5.0.2.1..1.2.3.5
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, Apr 23 2012
EXTENSIONS
a(7)-a(11) from Andrew Howroyd, Apr 23 2018
STATUS
approved