OFFSET
1,4
COMMENTS
Diagonal 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....0....2....2....2....2....2....0....2....2....0....2
..0....3....3....0....2....2....3....3....0....3....1....2....0....3....2....0
..2....2....1....3....0....3....4....0....3....0....0....3....3....1....1....1
..1....4....4....4....3....2....1....2....2....4....3....4....1....2....3....3
CROSSREFS
KEYWORD
nonn,more
AUTHOR
R. H. Hardin, Aug 09 2012
STATUS
approved