A185883 1/729 the number of (n+2) X 3 0..2 arrays with no 3 X 3 subblock trace equal to any horizontal or vertical neighbor 3 X 3 subblock trace.

27, 588, 12900, 282672, 6195480, 135783240, 2975926392, 65222436072, 1429460497272, 31329049201704, 686629243183416, 15048644047773288, 329816550981847032, 7228488945306025128, 158424591792311309496

Offset

1,1

Comments

Column 1 of A185891.

Links

R. H. Hardin, Table of n, a(n) for n = 1..200

Formula

Empirical: a(n) = 10*a(n-1) + 221*a(n-2) + 846*a(n-3) + 756*a(n-4).

Empirical g.f.: 3*x*(9 + 106*x + 351*x^2 + 294*x^3) / (1 - 10*x - 221*x^2 - 846*x^3 - 756*x^4). - Colin Barker, Apr 17 2018

Example

Some solutions for 4 X 3:
..0..1..1....0..1..1....0..0..1....0..0..1....0..0..0....0..0..1....0..1..1
..0..1..0....1..1..1....1..2..0....1..0..0....1..1..1....0..0..1....1..0..0
..0..0..1....0..2..0....0..2..0....1..0..0....2..2..1....2..2..2....1..0..1
..1..2..1....1..0..2....0..0..2....0..2..1....0..0..1....2..1..2....0..1..1

Crossrefs

Cf. A185891.

Sequence in context: A076008 A232944 A185891 * A212670 A099753 A231292

Adjacent sequences: A185880 A185881 A185882 * A185884 A185885 A185886

Keyword

nonn

Author

R. H. Hardin, Feb 05 2011

Status

approved