OFFSET
1,1
COMMENTS
Column 6 of A207068.
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..210
FORMULA
Empirical: a(n) = (7/120)*n^6 + (147/40)*n^5 + (49/3)*n^4 + (91/8)*n^3 - (707/120)*n^2 - (91/20)*n.
Conjectures from Colin Barker, Jun 18 2018: (Start)
G.f.: 21*x*(1 + 14*x - 7*x^2 - 8*x^3 + 2*x^4) / (1 - x)^7.
a(n) = 7*a(n-1) - 21*a(n-2) + 35*a(n-3) - 35*a(n-4) + 21*a(n-5) - 7*a(n-6) + a(n-7) for n>7.
(End)
EXAMPLE
Some solutions for n=4:
..0..0..0..0..0..0....0..1..1..1..0..0....1..0..1..1..1..0....1..1..1..1..1..0
..1..0..1..1..1..0....1..0..1..1..1..0....0..1..1..1..1..0....0..0..0..0..0..0
..0..0..0..0..0..0....1..0..0..0..0..0....0..1..1..1..0..0....0..0..0..0..0..0
..0..0..0..0..0..0....1..0..0..0..0..0....0..0..0..0..0..0....0..0..0..0..0..0
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, Feb 14 2012
STATUS
approved