Number of n X n binary arrays symmetric about both diagonal and antidiagonal with all ones connected only in a 1100-1111-0001 pattern in any orientation.
A146851
Number of n X n binary arrays symmetric about both diagonal and antidiagonal with all ones connected only in a 1100-1111-0001 pattern in any orientation.
Terms
- a(0) =1a(1) =1a(2) =1a(3) =1a(4) =1a(5) =1a(6) =1a(7) =1a(8) =5a(9) =13a(10) =25a(11) =45a(12) =129a(13) =391a(14) =1245a(15) =4737a(16) =21985a(17) =95961a(18) =496289a(19) =2673135a(20) =16997063a(21) =114065803
External references
- oeis: A146851