OFFSET
1,1
COMMENTS
Column 3 of A224568.
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..210
FORMULA
Empirical: a(n) = 3*a(n-1) - 2*a(n-2) - 2*a(n-3) + 4*a(n-4) - 3*a(n-5) + 2*a(n-7) - a(n-8) for n>10.
Empirical g.f.: x*(512 - 1108*x + 254*x^2 + 967*x^3 - 1323*x^4 + 855*x^5 + 387*x^6 - 753*x^7 + 167*x^8 + 40*x^9) / ((1 - x)^3*(1 + x)*(1 - x - x^4)). - Colin Barker, Sep 01 2018
EXAMPLE
Some solutions for n=3:
..1..0..0..0..0..0....1..0..0..0..0..0....1..0..0..0..1..0....1..0..0..0..0..0
..1..0..0..0..0..0....1..0..0..0..0..0....1..0..0..0..0..0....1..0..0..0..0..0
..0..0..0..0..0..0....1..0..0..0..0..0....1..0..0..0..1..0....1..0..0..0..0..1
..0..0..0..0..0..0....0..0..0..0..0..0....1..0..0..0..1..0....0..0..0..0..0..1
..0..0..0..0..0..0....0..0..0..0..0..0....1..0..0..0..1..0....1..0..0..0..0..1
..0..1..1..1..1..1....0..0..0..1..1..1....0..0..0..0..1..0....0..0..0..0..0..1
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, Apr 10 2013
STATUS
approved