OFFSET
1,1
COMMENTS
Column 4 of A255660
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..210
FORMULA
Empirical: a(n) = 4*a(n-1) -4*a(n-3) +15*a(n-4) -24*a(n-5) -68*a(n-6) +136*a(n-7) -81*a(n-8) +40*a(n-9) -10*a(n-10) +4*a(n-11) -a(n-12)
EXAMPLE
Some solutions for n=4
..3....2....1....1....2....0....2....1....0....3....3....1....1....3....2....2
..0....1....3....2....1....3....2....3....2....0....1....3....0....0....2....1
..1....2....0....2....3....1....1....3....0....0....1....3....1....0....0....1
..1....2....2....1....3....1....3....1....1....1....2....1....1....0....1....3
..2....0....3....3....0....1....0....1....3....1....3....2....2....0....3....0
..2....3....1....3....2....2....3....1....3....1....3....1....2....1....1....0
..0....3....1....2....1....1....3....2....3....0....1....2....2....2....0....3
..0....1....2....0....3....1....0....3....0....0....1....1....1....3....1....2
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, Mar 01 2015
STATUS
approved