Numbers that are the same upside down (using only digits 0, 1, 6 and 9).

Terms

a(0) =0a(1) =1a(2) =11a(3) =69a(4) =96a(5) =101a(6) =111a(7) =609a(8) =619a(9) =906a(10) =916a(11) =1001a(12) =1111a(13) =1691a(14) =1961a(15) =6009a(16) =6119a(17) =6699a(18) =6969a(19) =9006a(20) =9116a(21) =9696a(22) =9966a(23) =10001a(24) =10101a(25) =11011a(26) =11111a(27) =16091a(28) =16191a(29) =19061