OFFSET
1,1
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..210
FORMULA
Empirical: a(n) = 5*a(n-1) - 9*a(n-2) + 7*a(n-3) - 2*a(n-4) for n>8.
Conjectures from Colin Barker, Dec 10 2018: (Start)
G.f.: x*(907 - 2760*x + 997*x^2 + 3624*x^3 - 4009*x^4 + 1208*x^5 - 7*x^6 + x^7) / ((1 - x)^3*(1 - 2*x)).
a(n) = (3/32)*(5280 + 697*2^n + 1840*n + 208*n^2) for n>4.
(End)
EXAMPLE
Some solutions for n=4:
..0..1..0..1..0..0....1..1..1..1..1..1....0..1..1..1..1..1....1..1..0..0..1..1
..0..1..0..1..0..0....1..1..1..1..1..1....0..0..0..0..0..0....1..1..0..0..0..0
..0..1..0..1..0..0....1..1..1..1..1..1....1..0..0..0..0..0....1..1..0..0..0..0
..1..1..0..1..0..0....1..1..1..1..1..1....1..0..0..0..0..0....0..0..0..0..0..0
..1..0..0..1..0..1....0..0..0..0..0..1....0..0..0..0..0..0....0..0..1..1..1..1
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, Dec 29 2014
STATUS
approved