OFFSET
1,1
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..210
FORMULA
Empirical: a(n) = 8*a(n-1) - 25*a(n-2) + 35*a(n-3) - 9*a(n-4) - 37*a(n-5) + 47*a(n-6) - 15*a(n-7) - 10*a(n-8) + 9*a(n-9) - 2*a(n-10).
Empirical g.f.: 2*x*(288 - 1506*x + 2843*x^2 - 1193*x^3 - 3324*x^4 + 5009*x^5 - 1866*x^6 - 1087*x^7 + 1094*x^8 - 256*x^9) / ((1 - x)^6*(1 + x)*(1 - 2*x)*(1 - x - x^2)). - Colin Barker, Nov 20 2018
EXAMPLE
Some solutions for n=4:
..1..0..0..0..0....1..0..0..1..0....0..0..1..0..1....0..0..0..0..0
..1..0..0..0..0....1..0..0..1..0....0..0..1..0..1....0..0..0..0..0
..1..0..0..0..1....1..0..0..1..0....0..0..1..0..1....0..0..0..0..0
..1..0..0..0..1....1..0..1..0..1....0..1..0..1..0....0..0..0..0..0
..1..0..0..1..0....1..0..1..0..1....0..1..0..1..1....0..0..0..0..1
..1..0..0..1..0....1..0..1..0..1....0..1..0..1..1....0..0..0..1..0
..1..0..1..0..1....1..1..0..1..0....0..1..0..1..1....0..1..1..0..1
..1..1..0..1..0....1..1..0..1..1....0..1..0..1..1....0..1..1..0..1
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, Nov 27 2014
STATUS
approved