Number of n X n binary arrays symmetric about both diagonal and antidiagonal with all ones connected only in a 1001-1001-1111 pattern in any orientation.
A147409
Number of n X n binary arrays symmetric about both diagonal and antidiagonal with all ones connected only in a 1001-1001-1111 pattern in any orientation.
Terms
- a(0) =1a(1) =1a(2) =1a(3) =1a(4) =1a(5) =1a(6) =1a(7) =1a(8) =1a(9) =3a(10) =7a(11) =13a(12) =21a(13) =31a(14) =61a(15) =147a(16) =365a(17) =1043a(18) =3041a(19) =10027a(20) =33377a(21) =115807a(22) =406723a(23) =1580475a(24) =6700609
External references
- oeis: A147409