Numbers k such that k and k^2 use only the digits 0, 2, 4 and 5.

Terms

a(0) =0a(1) =2a(2) =5a(3) =20a(4) =45a(5) =50a(6) =200a(7) =205a(8) =450a(9) =500a(10) =502a(11) =505a(12) =2000a(13) =2005a(14) =2050a(15) =2245a(16) =4500a(17) =5000a(18) =5002a(19) =5005a(20) =5020a(21) =5045a(22) =5050a(23) =20000a(24) =20005a(25) =20050a(26) =20500a(27) =20505a(28) =22450a(29) =45000