Numbers k such that k and k^2 use only the digits 0, 1, 3, 5 and 7.

Terms

a(0) =0a(1) =1a(2) =10a(3) =100a(4) =1000a(5) =10000a(6) =100000a(7) =130501a(8) =550501a(9) =1000000a(10) =1305010a(11) =5505010a(12) =7553501a(13) =10000000a(14) =10550501a(15) =13050100a(16) =55050100a(17) =55055001a(18) =57533501a(19) =57733501a(20) =73055001a(21) =75535010a(22) =100000000a(23) =105505010a(24) =130501000a(25) =131531501a(26) =550501000a(27) =550550010a(28) =575335010a(29) =575355001