1/4 the number of (n+1)X7 0..3 arrays with every 2X2 subblock having one or four distinct clockwise edge differences.

A209856

1/4 the number of (n+1)X7 0..3 arrays with every 2X2 subblock having one or four distinct clockwise edge differences.

Terms

    a(0) =492373a(1) =155490654a(2) =47417927307

External references