A268141 Number of nX4 arrays of permutations of 4 copies of 0..n-1 with every element equal to at least one diagonal or antidiagonal neighbor and the top left element equal to 0.

0, 3, 8, 672, 5760, 1411560, 25024320, 11908517040, 361147852800

Offset: 1

Author

R. H. Hardin, Jan 27 2016

Keywords

• nonn

Comments

Column 4 of A268142.

Examples

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

Crossrefs

Cf. A268142.