Numbers k such that k and k^2 use only the digits 0, 1, 4, 6 and 8.

Terms

a(0) =0a(1) =1a(2) =4a(3) =8a(4) =10a(5) =40a(6) =41a(7) =80a(8) =100a(9) =104a(10) =108a(11) =400a(12) =401a(13) =408a(14) =410a(15) =641a(16) =800a(17) =801a(18) =804a(19) =1000a(20) =1004a(21) =1008a(22) =1040a(23) =1080a(24) =4000a(25) =4001a(26) =4008a(27) =4010a(28) =4080a(29) =4100