OFFSET
1,1
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..210
FORMULA
Empirical: a(n) = (171/4)*n^4 + 390*n^3 + (5627/4)*n^2 + (3575/2)*n + 729.
Conjectures from Colin Barker, Nov 21 2018: (Start)
G.f.: x*(4356 - 8045*x + 7630*x^2 - 3644*x^3 + 729*x^4) / (1 - x)^5.
a(n) = 5*a(n-1) - 10*a(n-2) + 10*a(n-3) - 5*a(n-4) + a(n-5) for n>5.
(End)
EXAMPLE
Some solutions for n=4:
..1..1..1..2..2....0..0..0..0..0....2..2..2..0..1....2..0..0..0..0
..1..1..1..2..2....1..1..1..1..1....0..0..0..0..1....0..0..0..0..0
..1..1..1..2..2....1..1..1..1..1....0..0..0..0..1....1..1..1..1..1
..0..0..0..1..1....0..0..0..0..0....1..1..1..1..2....0..0..0..0..0
..0..0..1..2..2....0..0..2..2..2....1..1..1..1..2....0..0..0..0..0
..0..0..1..2..2....0..0..2..2..2....0..0..0..0..1....0..1..1..1..2
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, Nov 27 2014
STATUS
approved