Number of (n+1)X4 0..3 arrays with every 2X2 subblock having two distinct values, and new values 0..3 introduced in row major order.

A209809

Number of (n+1)X4 0..3 arrays with every 2X2 subblock having two distinct values, and new values 0..3 introduced in row major order.

Terms

    a(0) =173a(1) =2721a(2) =43209a(3) =712829a(4) =11912459a(5) =201392025a(6) =3428713825a(7) =58668627061

External references