Number of n X n binary arrays symmetric about both diagonal and antidiagonal with all ones connected only in a 1100-0111-1100 pattern in any orientation.

A146678

Number of n X n binary arrays symmetric about both diagonal and antidiagonal with all ones connected only in a 1100-0111-1100 pattern in any orientation.

Terms

    a(0) =1a(1) =1a(2) =1a(3) =1a(4) =1a(5) =1a(6) =1a(7) =1a(8) =4a(9) =7a(10) =14a(11) =21a(12) =42a(13) =97a(14) =337a(15) =907a(16) =3367a(17) =9291a(18) =36318a(19) =129686a(20) =674043a(21) =2983615a(22) =17944470a(23) =88292506a(24) =606666014a(25) =3595901269a(26) =30553144868a(27) =219341547026

External references