Numbers k such that k and k^2 use only the digits 0, 1, 3 and 5.

Terms

a(0) =0a(1) =1a(2) =10a(3) =100a(4) =1000a(5) =10000a(6) =100000a(7) =550501a(8) =1000000a(9) =5505010a(10) =10000000a(11) =55050100a(12) =55055001a(13) =100000000a(14) =550501000a(15) =550550010a(16) =1000000000a(17) =1000550501a(18) =1005055001a(19) =5505010000a(20) =5505500100a(21) =10000000000a(22) =10005505010a(23) =10050550010a(24) =55050100000a(25) =55055001000a(26) =100000000000a(27) =100000550501a(28) =100055050100a(29) =100505500100