Number of n X n binary arrays symmetric under horizontal and vertical reflection with all ones connected only in a 1000-1100-0111-0010 pattern in any orientation.
A147149
Number of n X n binary arrays symmetric under horizontal and vertical reflection with all ones connected only in a 1000-1100-0111-0010 pattern in any orientation.
Terms
- a(0) =1a(1) =1a(2) =1a(3) =1a(4) =1a(5) =1a(6) =1a(7) =1a(8) =9a(9) =9a(10) =33a(11) =33a(12) =121a(13) =121a(14) =1109a(15) =1109a(16) =21917a(17) =21917a(18) =638145a(19) =638145a(20) =19928333a(21) =19928333
External references
- oeis: A147149