Number of potential flows in n X n array with integer velocities in -3..3, i.e., number of n X n arrays with adjacent elements differing by no more than 3, counting arrays differing by a constant only once.

A068750

Number of potential flows in n X n array with integer velocities in -3..3, i.e., number of n X n arrays with adjacent elements differing by no more than 3, counting arrays differing by a constant only once.