Number of nX2 arrays containing 2 copies of 0..n-1 with no equal horizontal or vertical neighbors.

A264952

Number of nX2 arrays containing 2 copies of 0..n-1 with no equal horizontal or vertical neighbors.

Terms

    a(0) =0a(1) =2a(2) =12a(3) =504a(4) =22320a(5) =1521360a(6) =140394240a(7) =17034433920

External references