Number of n X n binary arrays symmetric under horizontal and vertical reflection with all ones connected only in a 0100-1100-0111-0001 pattern in any orientation.
A147263
Number of n X n binary arrays symmetric under horizontal and vertical reflection with all ones connected only in a 0100-1100-0111-0001 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) =105a(13) =105a(14) =825a(15) =825a(16) =13503a(17) =13503a(18) =390699a(19) =390699a(20) =9339771a(21) =9339771
External references
- oeis: A147263