Number of n X n binary arrays symmetric about main diagonal with all ones connected only in a zee 1,1 1,2 2,2 2,3 in any orientation.

A145955

Number of n X n binary arrays symmetric about main diagonal with all ones connected only in a zee 1,1 1,2 2,2 2,3 in any orientation.

Terms

    a(0) =1a(1) =1a(2) =1a(3) =3a(4) =9a(5) =23a(6) =125a(7) =821a(8) =6239a(9) =71403a(10) =1048093a(11) =19913069a(12) =517074745a(13) =17642361171a(14) =795865550951

External references