OFFSET
1,2
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..210
FORMULA
Empirical: a(n) = 5*a(n-1) - 7*a(n-2) - 2*a(n-3) + 10*a(n-4) - 2*a(n-5) - 5*a(n-6) + a(n-7) + a(n-8) for n>10.
Empirical g.f.: x^2*(9 + 5*x - 43*x^2 - 27*x^3 + 63*x^4 + 47*x^5 - 33*x^6 - 25*x^7 + 8*x^8) / ((1 - x)^2*(1 - x - x^2)^3). - Colin Barker, Feb 13 2019
EXAMPLE
Some solutions for n=4:
..0..1..1. .0..1..1. .0..1..1. .0..1..0. .0..1..1. .0..1..0. .0..1..1
..1..0..0. .1..0..0. .1..0..0. .1..0..0. .1..0..1. .1..0..0. .0..0..1
..1..1..0. .0..1..0. .0..1..1. .0..1..0. .1..1..0. .0..1..1. .1..1..0
..1..0..1. .0..1..0. .1..1..0. .0..0..1. .1..0..1. .1..0..1. .0..0..1
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jan 05 2017
STATUS
approved