A263440 Number of nX2 arrays of permutations of 0..n*2-1 with each element moved a city block distance of 0 or 3.

1, 1, 4, 25, 125, 633, 2532, 10288, 48776, 233776, 1080228, 4996113, 23080949, 107157345, 501507348, 2345998289, 10947914825, 51111745065, 238823109920, 1116507049088, 5221116919456, 24414616690816, 114158428564416

Offset: 1

Author

R. H. Hardin, Oct 18 2015

Keywords

• nonn

Comments

Column 2 of A263442.

Examples

			Some solutions for n=4
..0..7....5..7....5..1....0..4....0..1....0..4....0..1....6..4....5..1....0..4
..2..6....2..6....2..3....2..6....7..6....7..6....7..3....2..3....7..6....2..3
..4..5....4..0....4..0....1..5....4..5....1..5....4..5....1..5....4..0....1..5
..3..1....3..1....6..7....3..7....3..2....3..2....6..2....0..7....3..2....6..7
		

Links

• R. H. Hardin, Table of n, a(n) for n = 1..210

Crossrefs

Cf. A263442.