OFFSET
1,1
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..210
FORMULA
Empirical: a(n) = 2*a(n-1) - a(n-2) + a(n-3) - a(n-4) - a(n-7) + a(n-8) -a(n-9) + a(n-10) + a(n-12) - a(n-13) for n>17.
Empirical g.f.: x*(2662 - 3830*x + 1310*x^2 - 2544*x^3 + 1148*x^4 - 164*x^5 + 30*x^6 + 2753*x^7 - 1112*x^8 + 2503*x^9 - 1622*x^10 - 233*x^11 - 2720*x^12 + 1520*x^13 + 221*x^14 + 61*x^15 + 5*x^16) / ((1 - x)^3*(1 + x)*(1 - x + x^2)*(1 + x^2)*(1 + x + x^2)*(1 - x^2 - x^3)). - Colin Barker, Sep 02 2018
EXAMPLE
Some solutions for n=2:
..1..0..0..0..0..0..0....1..0..0..0..0..0..1....1..1..0..0..0..0..0
..1..0..0..0..0..0..0....1..0..0..0..0..0..0....0..0..0..0..0..0..0
..0..0..0..0..0..0..0....1..0..0..0..0..0..0....0..0..1..1..1..0..0
..0..0..0..0..0..0..0....0..0..0..0..0..0..0....0..0..0..0..0..0..0
..1..0..0..0..0..0..0....1..0..0..0..0..0..1....0..0..0..0..0..0..0
..0..1..0..0..1..1..1....0..0..0..0..0..0..1....0..0..1..1..1..0..0
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, Apr 15 2013
STATUS
approved