OFFSET
1,1
COMMENTS
Column 2 of A296386.
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..210
FORMULA
Empirical: a(n) = 3*a(n-1) - a(n-2) + 6*a(n-3) - 6*a(n-4) + 6*a(n-5) - 5*a(n-6) + 3*a(n-7) - a(n-8).
Empirical g.f.: x*(1 + x - x^2)*(2 + 2*x + 2*x^3 - x^4 + x^5) / (1 - 3*x + x^2 - 6*x^3 + 6*x^4 - 6*x^5 + 5*x^6 - 3*x^7 + x^8). - Colin Barker, Mar 22 2018
EXAMPLE
Some solutions for n=5:
..1..0. .0..1. .0..0. .0..0. .0..1. .0..0. .1..0. .1..1. .1..1. .0..1
..1..0. .1..0. .0..0. .0..1. .0..1. .0..0. .1..0. .0..1. .0..0. .1..1
..1..0. .1..0. .1..0. .1..0. .0..0. .0..0. .0..1. .1..0. .1..0. .0..0
..0..0. .1..0. .1..1. .0..1. .0..1. .1..0. .0..1. .0..1. .1..1. .1..1
..1..1. .0..0. .0..1. .0..1. .1..1. .1..0. .0..1. .1..1. .0..1. .0..1
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, Dec 11 2017
STATUS
approved