Number of length-n binary strings having a unique border.

Terms

a(0) =0a(1) =2a(2) =2a(3) =8a(4) =14a(5) =32a(6) =62a(7) =130a(8) =254a(9) =528a(10) =1038a(11) =2102a(12) =4194a(13) =8436a(14) =16826a(15) =33756a(16) =67438a(17) =135076a(18) =270022a(19) =540410a(20) =1080542a(21) =2161904a(22) =4323226a(23) =8647964a(24) =17294978a(25) =34592956a(26) =69183794a(27) =138373842a(28) =276743558a(29) =553499312