OFFSET
1,1
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..210
FORMULA
Empirical: a(n) = 12*a(n-1) - 40*a(n-2) + 8*a(n-3) + 92*a(n-4) - 32*a(n-5) - 64*a(n-6) for n>7.
Empirical g.f.: x*(13 - 80*x + 129*x^2 - 28*x^3 - 20*x^4 - 48*x^5 + 4*x^6) / (1 - 6*x + 2*x^2 + 8*x^3)^2. - Colin Barker, Jan 18 2019
EXAMPLE
Some solutions for n=4:
..1..1..0..0. .1..0..0..0. .0..0..1..0. .0..0..0..0. .0..0..0..1
..0..0..0..0. .0..0..1..0. .1..0..1..0. .0..0..1..0. .1..0..0..0
..1..0..0..0. .0..0..0..0. .0..0..0..0. .0..0..0..0. .0..1..0..0
..0..0..0..1. .0..0..1..1. .0..0..0..0. .0..0..0..0. .0..1..0..1
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, Feb 19 2016
STATUS
approved