OFFSET
1,1
COMMENTS
Row 2 of A209100.
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..210
FORMULA
Empirical: a(n) = 8*a(n-1) - 8*a(n-2) for n>3.
Empirical g.f.: x*(2 - 5*x + 4*x^2) / (1 - 8*x + 8*x^2). - Colin Barker, Jul 08 2018
EXAMPLE
Some solutions for n=4:
..0..0..1..2....0..0..1..1....0..0..0..1....0..0..1..1....0..0..0..0
..1..2..0..0....2..0..0..1....2..1..0..2....1..0..2..0....1..1..2..0
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, Mar 05 2012
STATUS
approved