OFFSET
1,1
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..210
FORMULA
Empirical: a(n) = 9*a(n-1) - 8*a(n-2) - 72*a(n-3) + 96*a(n-4) + 128*a(n-5) - 128*a(n-6) - 64*a(n-7) for n>8.
Empirical g.f.: x*(125 - 401*x - 716*x^2 + 2512*x^3 - 240*x^4 - 2192*x^5 + 512*x^6 + 512*x^7) / ((1 - 2*x)*(1 - 2*x - 4*x^2)*(1 - 5*x - 12*x^2 + 16*x^3 + 8*x^4)). - Colin Barker, Dec 11 2018
EXAMPLE
Some solutions for n=4:
..1..1..1..1....1..0..0..0....1..1..1..1....0..0..0..1....0..0..1..1
..0..1..1..1....1..1..1..1....0..0..0..0....1..1..1..1....0..0..1..0
..0..1..0..0....1..0..0..1....0..0..0..0....0..1..1..1....0..0..1..1
..0..1..0..0....1..1..1..1....1..1..1..1....1..1..1..1....1..1..1..0
..1..1..1..1....0..0..1..1....0..0..1..0....1..1..1..0....0..1..1..1
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, Dec 30 2014
STATUS
approved