OFFSET
1,1
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..210
FORMULA
Empirical: a(n) = 5*a(n-1) - 4*a(n-2) - 11*a(n-3) + 9*a(n-4) + 12*a(n-5) + 12*a(n-6) - 34*a(n-7) - 8*a(n-8) + 28*a(n-9) - 8*a(n-10) for n>11.
Empirical g.f.: x*(96 - 338*x - 122*x^2 + 1123*x^3 - 34*x^4 - 626*x^5 - 1907*x^6 + 1306*x^7+ 1728*x^8 - 1488*x^9 + 288*x^10) / ((1 - x)*(1 + x)*(1 - 2*x)*(1 - 3*x + x^2)*(1 - 2*x^2)*(1 - 2*x^3)). - Colin Barker, Dec 05 2018
EXAMPLE
Some solutions for n=4:
..0..1..0..1....0..1..1..0....0..1..1..0....0..0..1..1....0..1..1..0
..0..2..0..2....2..3..3..0....2..3..3..2....2..3..2..3....0..2..2..3
..1..2..1..2....2..1..1..2....0..1..1..2....2..3..2..3....3..1..1..3
..1..0..1..0....0..3..3..0....0..3..3..0....0..1..0..1....0..2..2..0
..3..0..3..0....0..1..1..2....2..1..1..2....0..1..0..1....3..1..1..3
..3..1..3..1....2..3..3..2....2..3..3..2....2..3..2..3....3..2..2..0
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, Dec 20 2014
STATUS
approved