Number of n X n binary arrays symmetric under horizontal and vertical reflection with all ones connected only either two adjacent vertically or two adjacent horizontally.
A145775
Number of n X n binary arrays symmetric under horizontal and vertical reflection with all ones connected only either two adjacent vertically or two adjacent horizontally.
Terms
- a(0) =1a(1) =1a(2) =1a(3) =4a(4) =10a(5) =25a(6) =98a(7) =304a(8) =1809a(9) =7930a(10) =72506a(11) =400613a(12) =5713422a(13) =40142648a(14) =888016669a(15) =8057185631a(16) =274304468798
External references
- oeis: A145775