Number of n X n binary arrays symmetric about both diagonal and antidiagonal with all ones connected only in a 1101-0111-0100 pattern in any orientation.

A146859

Number of n X n binary arrays symmetric about both diagonal and antidiagonal with all ones connected only in a 1101-0111-0100 pattern in any orientation.

Terms

    a(0) =1a(1) =1a(2) =1a(3) =1a(4) =1a(5) =1a(6) =1a(7) =3a(8) =5a(9) =15a(10) =25a(11) =43a(12) =109a(13) =409a(14) =1219a(15) =6135a(16) =18923a(17) =91055a(18) =376333a(19) =2366771a(20) =12618279a(21) =101741365

External references