A266207 Number of nX2 arrays containing 2 copies of 0..n-1 with no element plus any horizontal, vertical, diagonal or antidiagonal neighbor equal to n-1.

0, 0, 0, 8, 544, 20976, 3124800, 269723136, 61919980032, 9210279970560, 2897383466019840

Offset

1,4

Comments

Column 2 of A266208.

Links

Table of n, a(n) for n=1..11.

Example

Some solutions for n=6
..0..2....2..0....2..1....0..2....2..1....2..4....5..3....5..4....1..2....3..0
..1..1....2..4....0..0....0..1....2..0....0..2....4..3....3..5....0..0....4..4
..3..0....0..4....4..4....1..3....4..4....4..0....4..0....3..1....4..2....2..5
..3..4....3..3....3..3....3..5....5..5....3..3....2..0....0..1....5..4....2..5
..4..5....5..5....5..5....4..5....3..1....5..1....2..1....0..2....3..3....1..1
..2..5....1..1....2..1....2..4....0..3....1..5....5..1....2..4....5..1....0..3

Crossrefs

Cf. A266208.

Sequence in context: A089671 A112035 A200706 * A027536 A334255 A174252

Adjacent sequences: A266204 A266205 A266206 * A266208 A266209 A266210

Keyword

nonn

Author

R. H. Hardin, Dec 23 2015

Status

approved