OFFSET
1,1
COMMENTS
Column 3 of A268180.
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..210
FORMULA
Empirical: a(n) = 108*a(n-1) -2343*a(n-2) -95508*a(n-3) +3418760*a(n-4) +23547420*a(n-5) -1342943052*a(n-6) -883192104*a(n-7) +173217160160*a(n-8) -342228942720*a(n-9) -5613350923584*a(n-10) +8457106112640*a(n-11) +55966350739968*a(n-12) -69629468894208*a(n-13) -198751111188480*a(n-14) +222436679786496*a(n-15) +215814907920384*a(n-16) -228509902503936*a(n-17) for n>19
EXAMPLE
Some solutions for n=3
..0..1..1....0..1..0....0..1..2....0..1..2....0..1..0....0..0..1....0..1..1
..2..3..1....1..0..2....3..2..2....3..2..0....1..1..0....0..0..2....2..2..2
..1..3..2....3..0..3....3..1..3....3..2..1....1..2..1....1..3..2....0..3..2
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jan 28 2016
STATUS
approved