A206066 Number of (n+1) X 3 0..2 arrays with every 2 X 3 or 3 X 2 subblock having exactly three clockwise edge increases.

150, 606, 3330, 18534, 103194, 574182, 3193722, 17762598, 98788410, 549418086, 3055619322, 16993990566, 94512979386, 525638931174, 2923368683130, 16258469332518, 90422335862586, 502888596377958, 2796841487745018

Offset

1,1

Comments

Column 2 of A206072.

Links

R. H. Hardin, Table of n, a(n) for n = 1..210

Formula

Empirical: a(n) = 7*a(n-1) - 8*a(n-2) for n>6.

Empirical g.f.: 6*x*(25 - 74*x + 48*x^2 + 12*x^3 + 16*x^4 + 16*x^5) / (1 - 7*x + 8*x^2). - Colin Barker, Jun 13 2018

Example

Some solutions for n=4:
..1..0..0....0..0..1....2..1..0....1..2..0....0..1..0....0..1..2....2..0..0
..0..2..1....2..1..2....0..2..1....1..0..2....0..2..1....2..1..1....1..2..1
..1..0..2....0..2..0....1..0..2....0..1..0....1..0..2....1..0..2....2..1..2
..2..1..0....1..0..2....2..1..0....1..2..1....0..2..0....2..1..0....1..0..2
..1..0..1....2..1..0....0..2..1....0..0..2....1..0..1....0..2..1....2..1..0

Crossrefs

Cf. A206072.

Sequence in context: A211550 A212465 A273322 * A140671 A054558 A250544

Adjacent sequences: A206063 A206064 A206065 * A206067 A206068 A206069

Keyword

nonn

Author

R. H. Hardin, Feb 03 2012

Status

approved