A223144 Number of nX2 0..2 arrays with no more than floor(nX2/2) elements equal to at least one horizontal, vertical or antidiagonal neighbor, with new values introduced in row major 0..2 order

1, 7, 31, 187, 990, 5721, 32155, 185667, 1068413, 6209614, 36152732, 211488161, 1240108650, 7292753853, 42976317875, 253780411459, 1501160467318, 8893657851979, 52763660745169, 313428125418614, 1863953435747000

Offset

1,2

Comments

Column 2 of A223149

Links

R. H. Hardin, Table of n, a(n) for n = 1..192

Example

Some solutions for n=3
..0..0....0..1....0..1....0..1....0..1....0..1....0..1....0..1....0..1....0..1
..1..0....1..2....2..2....2..2....1..0....2..1....2..0....0..2....2..0....2..1
..2..1....0..1....0..2....2..0....2..1....1..2....2..2....1..0....2..1....0..1

Crossrefs

Sequence in context: A139151 A139060 A324621 * A155521 A201116 A329944

Adjacent sequences: A223141 A223142 A223143 * A223145 A223146 A223147

Keyword

nonn

Author

R. H. Hardin Mar 16 2013

Status

approved