OFFSET
1,1
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..210
FORMULA
Empirical: a(n) = 4*a(n-1) + 26*a(n-2) + 22*a(n-3) - 43*a(n-4) - a(n-5) + 7*a(n-6) - a(n-7) - a(n-8) for n>9.
Empirical g.f.: x*(7 + 38*x + 51*x^2 - 50*x^3 - 93*x^4 + 50*x^5 + 2*x^6 - 10*x^7 + x^8) / ((1 - 7*x - 5*x^2 - x^3)*(1 + 3*x - 6*x^3 + 4*x^4 - x^5)). - Colin Barker, Feb 26 2019
EXAMPLE
Some solutions for n=5:
..0..1..1..0. .1..1..0..1. .1..1..1..0. .0..1..1..0. .0..0..1..1
..1..0..0..1. .0..0..1..1. .0..1..0..1. .1..1..0..0. .0..1..0..1
..0..1..1..0. .0..0..1..1. .1..0..1..0. .0..1..0..0. .1..0..1..1
..1..0..0..0. .0..0..0..0. .0..1..0..0. .1..0..1..0. .0..0..0..1
..1..1..1..0. .0..1..1..0. .0..1..1..0. .1..1..0..0. .1..1..1..0
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, Dec 28 2017
STATUS
approved