Number of n X n binary arrays symmetric about both diagonal and antidiagonal with all ones connected only in a 1100-0111-0011 pattern in any orientation.

A147213

Number of n X n binary arrays symmetric about both diagonal and antidiagonal with all ones connected only in a 1100-0111-0011 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) =39a(11) =117a(12) =361a(13) =955a(14) =3303a(15) =16663a(16) =85069a(17) =434621a(18) =2513479a(19) =17082851a(20) =120871405a(21) =925679621

External references