A267544 Number of nX2 arrays containing 2 copies of 0..n-1 with no element 1 greater than its north, west or southeast neighbor modulo n and the upper left element equal to 0.

1, 0, 1, 27, 555, 24981, 1825761, 184975696, 24714858112, 4188322485532, 875632389820566

Offset

1,4

Comments

Column 2 of A267546.

Links

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

Example

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

Crossrefs

Cf. A267546.

Sequence in context: A051561 A163197 A347591 * A061914 A076008 A232944

Adjacent sequences: A267541 A267542 A267543 * A267545 A267546 A267547

Keyword

nonn

Author

R. H. Hardin, Jan 16 2016

Status

approved