Number of n X n binary arrays symmetric under 90 degree rotation with all ones connected only in a 11100-00100-00111 pattern in any orientation.
A147253
Number of n X n binary arrays symmetric under 90 degree rotation with all ones connected only in a 11100-00100-00111 pattern in any orientation.
Terms
- a(0) =1a(1) =1a(2) =1a(3) =1a(4) =1a(5) =1a(6) =1a(7) =1a(8) =11a(9) =17a(10) =41a(11) =57a(12) =231a(13) =453a(14) =1543a(15) =3457a(16) =18427a(17) =50015a(18) =289401a(19) =862907a(20) =5771143a(21) =20904685a(22) =158696163a(23) =662519097
External references
- oeis: A147253