A268158 Number of nX4 arrays of permutations of 4 copies of 0..n-1 with every element equal to at least one vertical or antidiagonal neighbor and the top left element equal to 0.

0, 3, 14, 906, 23592, 3304920, 334738800, 79401782880

Offset

1,2

Comments

Column 4 of A268159.

Links

Table of n, a(n) for n=1..8.

Example

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

Crossrefs

Cf. A268159.

Sequence in context: A305453 A305016 A316682 * A367674 A050645 A048568

Adjacent sequences: A268155 A268156 A268157 * A268159 A268160 A268161

Keyword

nonn

Author

R. H. Hardin, Jan 27 2016

Status

approved