OFFSET
1,5
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..210
FORMULA
Empirical: a(n) = 12*a(n-1) - 54*a(n-2) + 124*a(n-3) - 204*a(n-4) + 288*a(n-5) - 248*a(n-6) + 240*a(n-7) - 96*a(n-8) + 64*a(n-9).
Empirical g.f.: 4*x^5*(1 - 2*x) / (1 - 4*x + 2*x^2 - 4*x^3)^3. - Colin Barker, Feb 21 2019
EXAMPLE
All solutions for n=5:
..0..0. .0..0. .0..0. .0..0
..1..0. .0..1. .1..0. .0..1
..0..0. .0..0. .0..0. .0..0
..0..1. .1..0. .1..0. .0..1
..0..0. .0..0. .0..0. .0..0
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, Mar 13 2017
STATUS
approved