1/120 the number of (n+1)X7 0..4 arrays with every 2X2 subblock containing four distinct values.

A183619

1/120 the number of (n+1)X7 0..4 arrays with every 2X2 subblock containing four distinct values.

Terms

    a(0) =7776a(1) =446976a(2) =25713200a(3) =1498220176a(4) =87799260864

External references