Number of bicolored cyclic patterns n X n.

Terms

a(0) =0a(1) =2a(2) =3a(3) =10a(4) =15a(5) =35a(6) =63a(7) =138a(8) =255a(9) =527a(10) =1023a(11) =2083a(12) =4095a(13) =8255a(14) =16383a(15) =32906a(16) =65535a(17) =131327a(18) =262143a(19) =524815a(20) =1048575a(21) =2098175a(22) =4194303a(23) =8390691a(24) =16777215a(25) =33558527a(26) =67108863a(27) =134225983a(28) =268435455a(29) =536887295