Number of n X n binary arrays symmetric about both diagonal and antidiagonal with all ones connected only in a 1000-1000-1111-0010 pattern in any orientation.
A147111
Number of n X n binary arrays symmetric about both diagonal and antidiagonal with all ones connected only in a 1000-1000-1111-0010 pattern in any orientation.
Terms
- a(0) =1a(1) =1a(2) =1a(3) =1a(4) =1a(5) =1a(6) =1a(7) =1a(8) =3a(9) =9a(10) =19a(11) =33a(12) =77a(13) =215a(14) =619a(15) =1943a(16) =7543a(17) =33395a(18) =150047a(19) =720261a(20) =3747953a(21) =21922241
External references
- oeis: A147111