OFFSET
1,1
COMMENTS
Same recurrences as A228285 except in addition this smaller one for this column.
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..210
FORMULA
Empirical: a(n) = 3*a(n-1) + 15*a(n-2) + 16*a(n-3) - 11*a(n-4) - 20*a(n-5) + 19*a(n-6) - 8*a(n-7) + a(n-9).
Empirical g.f.: x*(5 + 4*x - 5*x^2 - 18*x^3 + 16*x^4 - 6*x^5 + x^7) / (1 - 3*x - 15*x^2 - 16*x^3 + 11*x^4 + 20*x^5 - 19*x^6 + 8*x^7 - x^9). - Colin Barker, Sep 11 2018
EXAMPLE
Some solutions for n=4:
..1..0..1..0..0....1..0..0..0..0....1..0..0..0..0....1..0..1..0..0
..0..0..0..1..0....0..0..0..0..1....0..0..0..0..0....0..0..0..1..0
..1..0..0..0..1....1..0..0..0..0....1..0..0..0..0....1..0..0..0..0
..0..0..1..0..0....0..0..0..0..0....0..0..0..1..0....0..1..0..0..1
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, Aug 22 2013
STATUS
approved