Number of nX4 nonnegative integer arrays with new values 0 upwards introduced in row major order and no element equal to more than one of its immediate leftward or upward or right-upward antidiagonal neighbors.

A208579

Number of nX4 nonnegative integer arrays with new values 0 upwards introduced in row major order and no element equal to more than one of its immediate leftward or upward or right-upward antidiagonal neighbors.

Terms

    a(0) =15a(1) =3024a(2) =2946848a(3) =7289707650

External references