Number of n X n binary arrays symmetric about both diagonal and antidiagonal with all ones connected only in a 2 X 2 elbow 1,1 1,2 2,1 in any orientation.
A145939
Number of n X n binary arrays symmetric about both diagonal and antidiagonal with all ones connected only in a 2 X 2 elbow 1,1 1,2 2,1 in any orientation.
Terms
- a(0) =1a(1) =1a(2) =3a(3) =5a(4) =15a(5) =39a(6) =133a(7) =511a(8) =2773a(9) =14873a(10) =106373a(11) =810293a(12) =8275081a(13) =88902809a(14) =1280398135a(15) =19384764865a(16) =392921704943
External references
- oeis: A145939