Number of (n+2) X 3 0..3 arrays with every 3 X 3 subblock having three equal elements in a row horizontally, vertically or nw-to-se diagonally exactly one way, and new values 0..3 introduced in row major order.

A204880

Number of (n+2) X 3 0..3 arrays with every 3 X 3 subblock having three equal elements in a row horizontally, vertically or nw-to-se diagonally exactly one way, and new values 0..3 introduced in row major order.