%I #4 Nov 21 2015 08:19:24
%S 1,1,4,28,176,1600,16128,124416,1446336,35831808,1074954240,
%T 27136622592,711858585600,16840949760000,456855552000000,
%U 22466543616000000
%N Number of nX2 arrays of permutations of 0..n*2-1 with rows nondecreasing modulo 3 and columns nondecreasing modulo 6.
%C Column 2 of A264709.
%e Some solutions for n=6
%e ..0..6....9..6....0..6....6..0....0..6....0..7....6..0....6..0....6..3....6..7
%e ..9..1....3..0....9..1....1..2....7..1....6..1....7..1....1..8....0..9....0..2
%e ..3..7....4..7....3..7....7..8....2..8....2..8....2..8....7..2....1..4....1..8
%e ..4..2...10..1...10..2....9..4....3.10....9..3....9..3....3..4....7.10....9..3
%e .10..8....5..2....4..8....3.10....9.11...10..4....4..5....9.10....2..5...10.11
%e ..5.11...11..8....5.11....5.11....4..5...11..5...10.11....5.11....8.11....4..5
%Y Cf. A264709.
%K nonn
%O 1,3
%A _R. H. Hardin_, Nov 21 2015