A267616 Number of nX4 arrays of permutations of 4 copies of 0..n-1 with every element equal to at least one horizontal or antidiagonal neighbor and the top left element equal to 0.

1, 4, 42, 906, 33120, 1839720, 144491760, 15248903040, 2081942352000

Offset

1,2

Comments

Column 4 of A267617.

Links

Table of n, a(n) for n=1..9.

Example

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

Crossrefs

Cf. A267617.

Sequence in context: A241030 A143990 A352074 * A243809 A220180 A134356

Adjacent sequences: A267613 A267614 A267615 * A267617 A267618 A267619

Keyword

nonn

Author

R. H. Hardin, Jan 18 2016

Status

approved