A199259 Number of 2n X 3 0..2 arrays with values 0..2 introduced in row major order, the number of instances of each value within one of each other, and every element equal to exactly one horizontal or vertical neighbor.

3, 18, 114, 713, 4508, 28652, 183442, 1182513, 7674706, 50149664, 329879020, 2183961009, 14549033194, 97499792198, 657083735088, 4451886557217, 30312912452386, 207359582690700, 1424583104395390, 9826011131492859

Offset

1,1

Comments

2n elements of column 3 of A199261.

Links

R. H. Hardin, Table of n, a(n) for n = 1..71

Example

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

Crossrefs

Cf. A199261.

Sequence in context: A367045 A346578 A213099 * A163471 A054122 A213230

Adjacent sequences: A199256 A199257 A199258 * A199260 A199261 A199262

Keyword

nonn

Author

R. H. Hardin, Nov 04 2011

Status

approved