A266597 Number of nX2 arrays containing 2 copies of 0..n-1 with no element 1 greater than its north or northeast neighbor modulo n and the upper left element equal to 0.

1, 0, 2, 38, 1197, 64497, 4975742, 519665920, 70425165645, 12012958306121, 2518082525423953, 636165450001831755

Offset

1,3

Comments

Column 2 of A266599.

Links

Table of n, a(n) for n=1..12.

Example

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

Crossrefs

Cf. A266599.

Sequence in context: A230903 A246000 A266601 * A291821 A187544 A187545

Adjacent sequences: A266594 A266595 A266596 * A266598 A266599 A266600

Keyword

nonn

Author

R. H. Hardin, Jan 01 2016

Status

approved