Number of permutations of 0..floor((n*4-1)/2) on even squares of an n X 4 array such that each row and column of even squares is increasing.

A215288

Number of permutations of 0..floor((n*4-1)/2) on even squares of an n X 4 array such that each row and column of even squares is increasing.

Terms

    a(0) =1a(1) =6a(2) =30a(3) =280a(4) =2100a(5) =23100a(6) =210210a(7) =2522520a(8) =25729704a(9) =325909584a(10) =3585005424a(11) =47117214144a(12) =546896235600

External references