OFFSET
1,1
COMMENTS
Column 2 of A206383.
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..210
FORMULA
Empirical: a(n) = 36*a(n-1) - 377*a(n-2) + 1398*a(n-3) - 2064*a(n-4) + 1008*a(n-5).
Empirical g.f.: x*(85 - 1691*x + 8706*x^2 - 16640*x^3 + 10320*x^4) / ((1 - x)*(1 - 2*x)*(1 - 21*x)*(1 - 12*x + 24*x^2)). - Colin Barker, Jun 15 2018
EXAMPLE
Some solutions for n=4:
..0..0..1....0..0..0....0..0..0....0..0..1....0..0..0....0..0..0....0..0..0
..0..1..1....0..1..0....1..1..1....1..2..2....1..0..1....1..0..1....0..1..0
..0..0..1....3..0..0....0..0..0....1..3..0....1..1..1....0..2..0....1..1..1
..0..2..0....0..1..0....1..1..1....1..2..0....0..1..3....3..0..3....0..1..2
..1..0..0....2..0..2....2..2..2....0..2..3....1..3..2....2..3..3....1..3..1
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, Feb 07 2012
STATUS
approved