Number of nX3 array permutations with each element not moved or moved diagonally or antidiagonally by one.

A189274

Number of nX3 array permutations with each element not moved or moved diagonally or antidiagonally by one.

Terms

    a(0) =1a(1) =9a(2) =45a(3) =225a(4) =1125a(5) =5625a(6) =28125a(7) =140625a(8) =703125a(9) =3515625a(10) =17578125a(11) =87890625a(12) =439453125a(13) =2197265625a(14) =10986328125a(15) =54931640625a(16) =274658203125

External references