OFFSET
1,1
COMMENTS
Column 3 of A207589.
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..210
FORMULA
Empirical: a(n) = a(n-1) + a(n-2) + 4*a(n-3) - 2*a(n-4) - a(n-5) - 8*a(n-6) + a(n-7) - 3*a(n-8) + 3*a(n-9) -2 *a(n-10) - a(n-12) for n>14.
Empirical g.f.: 2*x*(3 + 15*x + 9*x^2 + 12*x^3 - 12*x^4 - 3*x^5 - 23*x^6 + 18*x^7 - 8*x^8 + 15*x^9 - 12*x^10 + 3*x^11 - 3*x^12 + 2*x^13) / ((1 - x - x^3)*(1 - x^2 - 4*x^3 - 2*x^4 - 2*x^5 + 2*x^6 - x^7 - x^9)). - Colin Barker, Mar 05 2018
EXAMPLE
Some solutions for n=4:
..1..1..1....0..1..1....0..1..1....0..1..0....1..1..1....1..1..0....1..0..0
..0..1..0....1..0..1....1..0..1....1..0..0....1..0..0....0..1..0....1..1..1
..1..0..0....0..1..0....1..1..0....0..1..0....0..1..1....1..0..0....0..1..1
..0..1..0....1..1..1....0..1..1....1..0..0....1..1..0....0..1..0....1..0..0
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, Feb 19 2012
STATUS
approved