Number of n X n binary arrays symmetric under 90 degree rotation with all ones connected only in a 3X3 el 1,1 1,2 1,3 2,3 3,3 in any orientation.
A146036
Number of n X n binary arrays symmetric under 90 degree rotation with all ones connected only in a 3X3 el 1,1 1,2 1,3 2,3 3,3 in any orientation.
Terms
- a(0) =1a(1) =1a(2) =1a(3) =1a(4) =1a(5) =1a(6) =11a(7) =17a(8) =43a(9) =77a(10) =281a(11) =645a(12) =3017a(13) =9213a(14) =61533a(15) =218977a(16) =1561879a(17) =6900617a(18) =60762405a(19) =333893691a(20) =3718652761a(21) =25349082469a(22) =352708796463
External references
- oeis: A146036