OFFSET
1,1
COMMENTS
Column 2 of A317773.
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..210
FORMULA
Empirical: a(n) = a(n-1) +2*a(n-3) -a(n-6)
Empirical: G.f.: -x*(x-1)*(x^4+3*x^3+4*x^2+3*x+2)/(1-x-2*x^3+x^6) . - R. J. Mathar, May 09 2023
EXAMPLE
Some solutions for n=5
..0..0. .0..1. .0..0. .0..0. .0..0. .0..0. .0..1. .0..0. .0..0. .0..1
..0..0. .0..0. .1..0. .0..0. .0..0. .0..0. .0..0. .0..0. .0..1. .0..0
..0..0. .0..0. .1..1. .0..0. .0..0. .0..1. .0..0. .1..0. .0..1. .0..0
..0..0. .0..0. .1..1. .0..0. .1..0. .0..1. .0..0. .1..1. .1..1. .1..0
..0..0. .1..0. .1..1. .1..0. .1..1. .1..1. .0..0. .1..1. .1..1. .1..1
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, Aug 06 2018
STATUS
approved