OFFSET
1,1
COMMENTS
Column 4 of A224568.
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..210
FORMULA
Empirical: a(n) = 4*a(n-1) - 7*a(n-2) + 8*a(n-3) - 6*a(n-4) + a(n-5) + 3*a(n-6) - 4*a(n-7) + 3*a(n-8) - a(n-9) for n>11.
Empirical g.f.: x*(739 - 2439*x + 3734*x^2 - 4057*x^3 + 2554*x^4 + 242*x^5 - 1880*x^6 + 2176*x^7 - 1413*x^8 + 314*x^9 + 28*x^10) / ((1 - x)^3*(1 + x^2)*(1 - x - x^4)). - Colin Barker, Sep 01 2018
EXAMPLE
Some solutions for n=3:
..1..0..0..0..0..0..1....1..0..0..0..0..0..0....1..1..1..0..0..0..0
..1..0..0..0..0..0..1....1..0..0..0..0..0..0....0..0..0..0..0..0..1
..1..0..0..0..0..0..1....1..0..0..0..0..0..0....0..0..0..0..0..0..1
..0..0..0..0..0..0..1....0..0..0..0..0..0..0....0..0..0..0..0..0..1
..1..0..0..0..0..0..1....1..0..0..0..0..0..0....0..0..0..0..0..0..1
..1..0..0..0..0..0..1....1..0..0..0..0..1..1....0..0..0..0..0..0..1
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, Apr 10 2013
STATUS
approved