OFFSET
1,1
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..210
FORMULA
Empirical: a(n) = 56*a(n-1) + 16*a(n-2) - 768*a(n-3) + 512*a(n-4).
Empirical g.f.: 64*x*(3151 + 188*x - 42720*x^2 + 28800*x^3) / ((1 + 4*x)*(1 - 60*x + 224*x^2 - 128*x^3)). - Colin Barker, Oct 11 2018
EXAMPLE
Some solutions for n=1:
..0..2..2....1..3..1....0..2..1....2..0..0....1..3..0....0..0..2....1..1..2
..1..2..0....2..0..3....3..1..1....3..1..3....2..1..2....1..0..3....3..0..2
..0..0..3....1..2..1....1..1..1....0..3..2....0..3..0....3..1..1....0..3..3
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, Dec 16 2013
STATUS
approved