Number of n X n binary arrays symmetric under horizontal and vertical reflection with all ones connected only in a 1000-1100-0111-0001 pattern in any orientation.
A147277
Number of n X n binary arrays symmetric under horizontal and vertical reflection with all ones connected only in a 1000-1100-0111-0001 pattern in any orientation.
Terms
- a(0) =1a(1) =1a(2) =1a(3) =1a(4) =1a(5) =1a(6) =1a(7) =1a(8) =9a(9) =9a(10) =33a(11) =33a(12) =137a(13) =137a(14) =1037a(15) =1037a(16) =14193a(17) =14193a(18) =449857a(19) =449857a(20) =13397625a(21) =13397625
External references
- oeis: A147277