OFFSET
1,1
COMMENTS
Column 5 of A205193.
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..210
FORMULA
Empirical: a(n) = 2*a(n-2) +a(n-6) for n>9.
Empirical g.f.: 4*x*(36 + 42*x + x^2 + 12*x^3 + 38*x^4 + 32*x^5 - 12*x^6 - 10*x^7 - 9*x^8) / (1 - 2*x^2 - x^6). - Colin Barker, Jun 11 2018
EXAMPLE
Some solutions for n=4:
..0..0..1..1..0..0....0..0..1..1..1..0....0..0..1..0..0..0....0..1..1..0..0..1
..0..0..1..1..0..0....1..1..0..1..1..1....0..1..0..0..0..1....0..1..1..0..0..0
..1..1..0..0..1..1....1..1..1..0..1..1....1..0..0..0..1..0....1..0..0..1..0..0
..1..1..0..0..1..1....0..1..1..1..0..0....0..0..0..1..0..0....1..0..0..0..1..0
..1..0..1..1..0..1....1..0..1..1..0..0....0..0..1..0..0..0....0..1..0..0..0..1
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jan 23 2012
STATUS
approved