OFFSET
1,1
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..105
FORMULA
Empirical: a(n) = 169*a(n-1) - 6387*a(n-2) + 71671*a(n-3) - 195052*a(n-4).
Conjectures from Colin Barker, Jan 03 2019: (Start)
G.f.: x*(33 - 3178*x + 57437*x^2 - 195052*x^3) / ((1 - 4*x)*(1 - 13*x)*(1 - 31*x)*(1 - 121*x)).
a(n) = (5*2^(1+2*n) + 11^(1+2*n) + 31*13^n + 29*31^n) / 81.
(End)
EXAMPLE
Some solutions for n=3:
..0..0..1..1..1....0..0..1..1..1....0..1..1..0..1....0..1..0..1..0
..0..0..1..1..1....0..0..0..0..1....0..0..1..1..1....1..0..1..1..0
..1..1..1..1..1....1..1..0..0..1....1..1..1..0..0....1..1..1..1..1
..1..1..1..1..1....0..1..0..1..0....0..1..0..1..0....0..1..1..0..1
..1..1..1..0..0....1..0..0..1..1....1..1..0..0..1....0..0..0..0..1
..1..1..1..0..0....1..0..0..1..1....1..1..1..1..1....0..0..1..1..1
..1..1..1..1..1....0..1..0..1..0....0..0..1..1..1....1..0..0..1..1
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, Oct 29 2015
STATUS
approved