1/120 the number of (n+1)X9 0..4 arrays with every 2X2 subblock containing four distinct values.

A183621

1/120 the number of (n+1)X9 0..4 arrays with every 2X2 subblock containing four distinct values.

Terms

    a(0) =279936a(1) =40034304a(2) =5726373936a(3) =833329037376

External references