Number of n X n binary arrays symmetric about both diagonal and antidiagonal with all ones connected only in a 1100-0111-0001 pattern in any orientation.
A146662
Number of n X n binary arrays symmetric about both diagonal and antidiagonal with all ones connected only in a 1100-0111-0001 pattern in any orientation.
Terms
- a(0) =1a(1) =1a(2) =1a(3) =1a(4) =1a(5) =1a(6) =1a(7) =3a(8) =9a(9) =19a(10) =41a(11) =133a(12) =407a(13) =1175a(14) =4535a(15) =22999a(16) =120797a(17) =662265a(18) =4237243a(19) =30856447a(20) =236921167a(21) =2042840001a(22) =20458483743a(23) =233380921399
External references
- oeis: A146662