Number of n X n symmetric binary arrays with rows, considered as binary numbers, in nondecreasing order, and all main diagonal and antidiagonal elements zero.
A162034
Number of n X n symmetric binary arrays with rows, considered as binary numbers, in nondecreasing order, and all main diagonal and antidiagonal elements zero.
Terms
- a(0) =1a(1) =1a(2) =2a(3) =3a(4) =10a(5) =23a(6) =161a(7) =643a(8) =10399a(9) =76674a(10) =2793020a(11) =39088170a(12) =3075920130a(13) =83293952237
External references
- oeis: A162034