OFFSET
1,1
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..210
FORMULA
Empirical: a(n) = 3*a(n-1) + a(n-2) + 3*a(n-3) - 6*a(n-4) - 8*a(n-5).
Empirical g.f.: x*(4 + 4*x - 3*x^2 - 14*x^3 - 8*x^4) / ((1 + x + 2*x^2)*(1 - 4*x + x^2 + 4*x^3)). - Colin Barker, Feb 21 2019
EXAMPLE
Some solutions for n=4:
..0..0..1..0. .1..0..0..1. .1..1..0..1. .0..0..0..0. .0..0..0..1
..0..0..0..0. .0..0..1..0. .0..1..0..1. .0..0..1..1. .0..1..0..1
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, Mar 14 2017
STATUS
approved