OFFSET
1,2
COMMENTS
Row 2 of A218842.
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) + 2*a(n-5) + 2*a(n-6) - 2*a(n-7) for n>9.
Empirical g.f.: x*(1 + 5*x + 5*x^2 + 7*x^3 + x^4 + 7*x^5 + x^6 - 2*x^8) / (1 - 2*x - x^2 - 3*x^3 - 2*x^5 - 2*x^6 + 2*x^7). - Colin Barker, Jul 24 2018
EXAMPLE
Some solutions for n=3:
..0..0..0....0..0..1....1..0..0....1..0..0....1..1..0....0..0..0....0..0..0
..0..1..1....0..0..1....1..0..1....0..1..1....0..0..0....0..0..1....1..0..0
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, Nov 07 2012
STATUS
approved