OFFSET
1,4
COMMENTS
Column 3 of A215401.
EXAMPLE
Some solutions for n=6:
..0....0....0....0....0....0....0....0....0....0....0....0....0....0....0....0
..1....1....1....1....1....1....1....1....1....1....1....1....1....1....1....1
..2....2....2....2....0....2....2....2....2....0....2....2....0....2....0....2
..3....3....1....3....2....0....0....1....1....2....0....0....2....3....2....0
..2....0....0....1....1....1....2....3....0....0....2....3....3....1....1....3
..1....2....2....3....3....3....3....2....3....3....1....1....2....2....2....2
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, Aug 09 2012
STATUS
approved