OFFSET
1,1
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..210
FORMULA
Empirical: a(n) = 192*a(n-4) + 608*a(n-6) + 400*a(n-8) for n>9.
Empirical g.f.: x*(81 + 312*x + 1240*x^2 + 4752*x^3 + 3576*x^4 + 12832*x^5 + 2784*x^6 + 8000*x^7 + 400*x^8) / (1 - 192*x^4 - 608*x^6 - 400*x^8). - Colin Barker, Oct 22 2018
EXAMPLE
Some solutions for n=5:
..0..1....2..1....0..2....1..1....0..0....0..1....2..2....0..0....1..0....0..2
..2..0....2..1....2..1....1..1....0..1....2..0....1..0....0..1....0..1....1..1
..1..2....0..1....0..1....2..1....0..1....0..2....0..2....1..0....1..2....0..1
..0..1....1..1....1..1....1..2....0..0....1..0....0..2....0..2....2..1....2..1
..0..1....1..2....0..2....0..1....2..0....0..1....1..0....0..0....0..0....0..2
..0..2....2..1....0..0....1..1....1..0....2..0....2..2....2..1....2..2....1..1
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, Feb 09 2014
STATUS
approved