OFFSET
1,1
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..210
FORMULA
Empirical: a(n) = 283*a(n-1) - 4251*a(n-2) + 13573*a(n-3) - 9604*a(n-4).
Empirical g.f.: x*(122 - 2112*x + 7803*x^2 - 8771*x^3) / ((1 - x)*(1 - 282*x + 3969*x^2 - 9604*x^3)). - Colin Barker, Oct 07 2018
EXAMPLE
Some solutions for n=2:
..0..1..0..0..2..0....0..0..1..1..3..3....0..1..3..2..2..2....0..1..0..2..0..1
..1..1..0..0..2..2....1..1..0..1..1..0....0..1..0..2..0..1....0..2..2..2..0..2
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, Dec 03 2013
STATUS
approved