Number of ways to reciprocally link elements of an nX4 array either to themselves or to exactly one horizontal, vertical or antidiagonal neighbor.

A220549

Number of ways to reciprocally link elements of an nX4 array either to themselves or to exactly one horizontal, vertical or antidiagonal neighbor.

Terms

    a(0) =5a(1) =108a(2) =1814a(3) =32173a(4) =565061a(5) =9943416a(6) =174911750a(7) =3077034244a(8) =54130248568a(9) =952245176313

External references