Number of n X n binary arrays symmetric under 90 degree rotation with all ones connected only in a 0110-1111-0110 pattern in any orientation.
A146923
Number of n X n binary arrays symmetric under 90 degree rotation with all ones connected only in a 0110-1111-0110 pattern in any orientation.
Terms
- a(0) =1a(1) =1a(2) =1a(3) =1a(4) =1a(5) =1a(6) =1a(7) =6a(8) =12a(9) =19a(10) =29a(11) =56a(12) =159a(13) =456a(14) =1350a(15) =3940a(16) =11848a(17) =42451a(18) =167584a(19) =713562a(20) =3187201
External references
- oeis: A146923