OFFSET
1,2
COMMENTS
Row 2 of A219421.
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..210
FORMULA
Empirical: a(n) = 2*a(n-1) + a(n-2) + 3*a(n-3) + 4*a(n-4) - 2*a(n-5) - 4*a(n-6) for n>8.
Empirical g.f.: x*(1 + 5*x + 5*x^2 + 7*x^3 + x^4 - 9*x^5 - 9*x^6 - 2*x^7) / ((1 + 2*x^2)*(1 - 2*x - 3*x^2 + x^3 + 2*x^4)). - Colin Barker, Jul 26 2018
EXAMPLE
Some solutions for n=3:
..0..0..0....1..0..1....0..0..1....0..0..0....1..0..0....0..0..1....0..0..0
..1..0..1....0..0..0....0..0..1....0..0..1....0..0..1....0..0..0....1..0..0
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, Nov 19 2012
STATUS
approved