A267620 Number of 4Xn arrays containing n copies of 0..4-1 with every element equal to at least one horizontal or antidiagonal neighbor and the top left element equal to 0.

0, 6, 48, 906, 59328, 2192682, 131218206, 6966218352, 394140187926, 22353391341810

Offset

1,2

Comments

Row 4 of A267617.

Links

Table of n, a(n) for n=1..10.

Example

Some solutions for n=4
..0..0..2..1....0..0..1..1....0..0..1..1....0..0..2..2....0..0..2..1
..2..2..1..3....2..2..0..0....2..2..2..2....1..1..3..3....2..2..1..3
..2..0..3..3....1..1..2..2....3..3..0..0....0..0..2..2....2..1..3..3
..0..3..1..1....3..3..3..3....1..1..3..3....3..3..1..1....1..3..0..0

Crossrefs

Cf. A267617.

Sequence in context: A291104 A108092 A052744 * A275334 A192769 A324461

Adjacent sequences: A267617 A267618 A267619 * A267621 A267622 A267623

Keyword

nonn

Author

R. H. Hardin, Jan 18 2016

Status

approved