1/4 the number of (n+1)X3 0..3 arrays with every 2X2 subblock having exactly two distinct clockwise edge differences.
A209547
1/4 the number of (n+1)X3 0..3 arrays with every 2X2 subblock having exactly two distinct clockwise edge differences.
Terms
- a(0) =20a(1) =105a(2) =562a(3) =3051a(4) =16582a(5) =90186a(6) =490547a(7) =2668340a(8) =14514612a(9) =78953457a(10) =429474356a(11) =2336164666a(12) =12707780399a(13) =69125130364a(14) =376012453568
External references
- oeis: A209547