OFFSET
1,3
COMMENTS
Column 7 of A221459
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..210
FORMULA
Empirical: a(n) = 22*a(n-1) -168*a(n-2) +440*a(n-3) +421*a(n-4) -2898*a(n-5) -924*a(n-6) +7944*a(n-7) +5931*a(n-8) -6610*a(n-9) -10562*a(n-10) -5040*a(n-11) -840*a(n-12)
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....1....1....2....0....2....0....0....2....1....1....0....2....2....0....2
..3....2....0....3....1....2....1....2....0....2....2....0....0....2....0....1
..0....1....0....3....2....1....2....2....3....0....2....2....1....3....2....1
..2....0....2....2....1....0....3....1....4....3....0....0....0....1....1....0
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin Jan 17 2013
STATUS
approved