A267832 Number of nX2 arrays containing 2 copies of 0..n-1 with every element equal to or 1 greater than any northeast neighbor modulo n and the upper left element equal to 0.

1, 3, 11, 54, 330, 2430, 20970, 207900, 2331000, 29189160, 404044200, 6129723600, 101181603600, 1805933329200, 34664949118800

Offset

1,2

Comments

Column 2 of A267836.

Links

Table of n, a(n) for n=1..15.

Example

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

Crossrefs

Cf. A267836.

Sequence in context: A302760 A054700 A009280 * A095707 A259105 A242952

Adjacent sequences: A267829 A267830 A267831 * A267833 A267834 A267835

Keyword

nonn

Author

R. H. Hardin, Jan 21 2016

Status

approved