A199252 Number of nX4 0..3 arrays with values 0..3 introduced in row major order, the number of instances of each value within one of each other, and no element equal to any horizontal or vertical neighbor.

1, 21, 447, 11223, 305863, 8862785, 267827143, 8351549833, 266729329121, 8681405364211, 286916350055011, 9603063714049169, 324843085529291745, 11088239688730868231, 381446891741918303003, 13211448568439934521121

Offset

1,2

Comments

Column 4 of A199256

Links

R. H. Hardin, Table of n, a(n) for n = 1..19

Example

Some solutions for n=5
..0..1..0..2....0..1..0..2....0..1..2..0....0..1..0..2....0..1..0..1
..1..3..2..0....1..2..3..0....1..3..0..2....1..3..2..0....2..3..2..0
..3..2..1..3....3..1..2..3....0..2..3..1....3..2..3..2....1..2..3..2
..2..0..2..1....0..2..3..1....1..0..1..3....1..0..1..0....0..3..1..0
..1..3..0..3....3..0..1..2....3..2..3..2....3..2..3..1....3..1..3..2

Crossrefs

Sequence in context: A041842 A215152 A383702 * A199197 A219419 A157014

Adjacent sequences: A199249 A199250 A199251 * A199253 A199254 A199255

Keyword

nonn

Author

R. H. Hardin, Nov 04 2011

Status

approved