OFFSET
1,2
COMMENTS
Row 3 of A221755.
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..73
FORMULA
Empirical: a(n) = 27*a(n-2) + 14*a(n-3) - 165*a(n-4) - 20*a(n-5) + 329*a(n-6) - 48*a(n-7) - 131*a(n-8) - 34*a(n-9) + 9*a(n-10).
Empirical g.f.: x^2*(4 - 65*x^2 - 12*x^3 + 235*x^4 - 30*x^5 - 161*x^6 - 38*x^7 + 10*x^8) / (1 - 27*x^2 - 14*x^3 + 165*x^4 + 20*x^5 - 329*x^6 + 48*x^7 + 131*x^8 + 34*x^9 - 9*x^10). - Colin Barker, Aug 10 2018
EXAMPLE
Some solutions for n=4:
..1..1..1..1....0..2..1..2....1..1..1..1....1..1..1..1....1..1..1..1
..0..2..0..1....1..0..2..0....0..2..1..1....0..2..1..2....1..1..1..1
..2..1..2..0....1..1..1..1....2..0..1..1....1..0..2..0....1..1..1..1
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jan 24 2013
STATUS
approved