OFFSET
1,2
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..210
FORMULA
Empirical: a(n) = a(n-1) + a(n-2) + 8*a(n-3) + a(n-4) - 2*a(n-6).
Empirical g.f.: x*(1 + 8*x + 9*x^2 + x^3 - 2*x^4 - 2*x^5) / (1 - x - x^2 - 8*x^3 - x^4 + 2*x^6). - Colin Barker, Feb 28 2019
EXAMPLE
Some solutions for n=5:
..0..0..0..1..1. .0..1..1..0..0. .0..0..0..1..0. .1..0..0..0..0
..1..1..0..0..0. .0..0..0..0..0. .0..0..0..0..1. .0..1..0..0..0
..0..0..0..1..1. .0..0..0..1..1. .0..0..0..0..0. .0..0..0..1..1
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, Dec 29 2017
STATUS
approved