Number of nX3 0..3 arrays with exactly floor(nX3/2) elements equal to at least one horizontal or vertical neighbor, with new values introduced in row major 0..3 order.

A222830

Number of nX3 0..3 arrays with exactly floor(nX3/2) elements equal to at least one horizontal or vertical neighbor, with new values introduced in row major 0..3 order.

Terms

    a(0) =0a(1) =32a(2) =2120a(3) =114782a(4) =5459252a(5) =346343088a(6) =17812721025

External references