OFFSET
1,1
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..210
FORMULA
Empirical: a(n) = a(n-1) + 4*a(n-2) + 6*a(n-3) + 3*a(n-4) - 3*a(n-6) + a(n-7) - 3*a(n-9) + a(n-11).
Empirical g.f.: x*(3 + 8*x + 9*x^2 + 2*x^3 - 4*x^4 - 2*x^5 + 2*x^6 - 3*x^7 - 3*x^8 + x^9 + x^10) / ((1 + x^2 - x^3)*(1 - x - 5*x^2 - 4*x^3 + x^4 - x^5 - 2*x^6 + x^7 + x^8)). - Colin Barker, Feb 23 2019
EXAMPLE
Some solutions for n=5:
..0..0..0. .0..1..1. .0..1..0. .1..1..0. .0..0..0. .0..0..0. .0..0..0
..0..0..0. .0..0..0. .0..1..0. .0..0..1. .0..1..0. .0..0..0. .1..1..0
..0..0..0. .1..0..0. .0..0..0. .0..1..0. .1..0..0. .1..0..0. .0..0..0
..0..0..0. .1..0..1. .0..0..0. .0..0..1. .0..1..0. .1..0..0. .0..0..1
..1..1..0. .0..1..0. .0..1..1. .0..1..0. .1..0..0. .0..1..1. .0..0..1
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, Dec 10 2017
STATUS
approved