Number of n X n binary arrays symmetric under 90 degree rotation with all ones connected only in a 1100-1111 pattern in any orientation.

A146230

Number of n X n binary arrays symmetric under 90 degree rotation with all ones connected only in a 1100-1111 pattern in any orientation.

Terms

    a(0) =1a(1) =1a(2) =1a(3) =1a(4) =1a(5) =3a(6) =13a(7) =33a(8) =61a(9) =183a(10) =597a(11) =2481a(12) =11129a(13) =55369a(14) =260691a(15) =1725489a(16) =11211005a(17) =97261999a(18) =792491905a(19) =8327148961a(20) =84267555083

External references