Number of n X n binary arrays symmetric under 90 degree rotation with all ones connected only in an em 1,1 1,2 2,2 2,3 3,3 in any orientation.
A146150
Number of n X n binary arrays symmetric under 90 degree rotation with all ones connected only in an em 1,1 1,2 2,2 2,3 3,3 in any orientation.
Terms
- a(0) =1a(1) =1a(2) =1a(3) =1a(4) =1a(5) =1a(6) =11a(7) =21a(8) =45a(9) =147a(10) =455a(11) =1443a(12) =6641a(13) =31711a(14) =178915a(15) =1031021a(16) =7211761a(17) =51418401a(18) =452868901a(19) =4229697689a(20) =48322007005a(21) =572003003167
External references
- oeis: A146150