OFFSET
1,1
COMMENTS
Column 1 of A184548.
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..200
FORMULA
Empirical: a(n) = (84 + 149*n + 36*n^2 + n^3) / 6. Corrected by Colin Barker, Apr 12 2018~
Conjectures from Colin Barker, Apr 12 2018: (Start)
G.f.: x*(45 - 91*x + 61*x^2 - 14*x^3) / (1 - x)^4.
a(n) = 4*a(n-1) - 6*a(n-2) + 4*a(n-3) - a(n-4) for n>4.
(End)
EXAMPLE
Some solutions for 4 X 3:
..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..1..1....0..0..0....0..0..1....0..0..1....0..1..1....0..0..1
..0..1..1....0..1..1....0..0..1....1..1..1....0..1..1....0..1..1....1..1..0
..1..0..1....1..0..0....0..1..0....1..1..1....1..1..0....0..1..1....1..1..1
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jan 16 2011
STATUS
approved