OFFSET
1,1
COMMENTS
Column 4 of A223556.
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..210
FORMULA
Empirical: a(n) = 41*a(n-1) - 16*a(n-2).
Conjectures from Colin Barker, Aug 21 2018: (Start)
G.f.: 9*x*(3 - 2*x) / (1 - 41*x + 16*x^2).
a(n) = 3*sqrt(3/11)*2^(-4-n)*((41-7*sqrt(33))^n*(-1+sqrt(33)) + (1+sqrt(33))*(41+7*sqrt(33))^n).
(End)
EXAMPLE
Some solutions for n=3:
..0..2..0..2....0..1..2..5....0..2..0..2....0..2..1..4....0..1..0..1
..0..1..0..2....2..1..4..5....1..2..0..2....5..4..5..2....2..1..2..1
..4..1..0..2....4..3..4..5....5..3..5..4....5..2..1..0....4..1..4..3
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, Mar 22 2013
STATUS
approved