OFFSET
1,1
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..210
FORMULA
Empirical: a(n) = 32*n^2 + 159*n + 128.
Conjectures from Colin Barker, Nov 15 2018: (Start)
G.f.: x*(319 - 383*x + 128*x^2) / (1 - x)^3.
a(n) = 3*a(n-1) - 3*a(n-2) + a(n-3) for n>3.
(End)
EXAMPLE
Some solutions for n=4:
..1..1..1..1..1....1..1..1..1..1....0..0..0..0..0....1..1..0..0..0
..1..1..1..1..1....0..0..0..0..0....1..1..1..1..1....0..0..0..0..0
..0..0..0..0..0....0..0..0..0..0....1..1..1..1..1....1..1..1..1..1
..0..0..0..0..0....0..0..0..0..0....1..1..1..1..1....0..0..0..0..0
..1..1..1..1..1....0..0..0..0..0....1..1..1..1..1....0..0..0..0..0
..0..0..0..0..1....1..1..1..1..1....1..1..1..1..1....1..1..1..1..1
..0..0..0..0..1....0..1..1..1..1....1..1..1..1..1....0..0..0..0..0
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, Nov 26 2014
STATUS
approved