Numbers k such that k and k^2 use only the digits 0, 2, 5 and 9.

Terms

a(0) =0a(1) =5a(2) =50a(3) =95a(4) =500a(5) =505a(6) =950a(7) =995a(8) =5000a(9) =5005a(10) =5050a(11) =5095a(12) =9500a(13) =9950a(14) =9995a(15) =50000a(16) =50005a(17) =50050a(18) =50095a(19) =50500a(20) =50950a(21) =95000a(22) =95005a(23) =99500a(24) =99950a(25) =99995a(26) =500000a(27) =500005a(28) =500050a(29) =500095