A264707 Number of nX2 arrays of permutations of 0..n*2-1 with rows nondecreasing modulo 3 and columns nondecreasing modulo 6.

1, 1, 4, 28, 176, 1600, 16128, 124416, 1446336, 35831808, 1074954240, 27136622592, 711858585600, 16840949760000, 456855552000000, 22466543616000000

Offset: 1

Author

R. H. Hardin, Nov 21 2015

Keywords

• nonn

Comments

Column 2 of A264709.

Examples

			Some solutions for n=6
..0..6....9..6....0..6....6..0....0..6....0..7....6..0....6..0....6..3....6..7
..9..1....3..0....9..1....1..2....7..1....6..1....7..1....1..8....0..9....0..2
..3..7....4..7....3..7....7..8....2..8....2..8....2..8....7..2....1..4....1..8
..4..2...10..1...10..2....9..4....3.10....9..3....9..3....3..4....7.10....9..3
.10..8....5..2....4..8....3.10....9.11...10..4....4..5....9.10....2..5...10.11
..5.11...11..8....5.11....5.11....4..5...11..5...10.11....5.11....8.11....4..5
		

Crossrefs

Cf. A264709.