Numbers k such that k and k^2 use only the digits 1, 2, 4, 5 and 6.

Terms

a(0) =1a(1) =2a(2) =4a(3) =5a(4) =11a(5) =12a(6) =15a(7) =16a(8) =21a(9) =25a(10) =46a(11) =65a(12) =112a(13) =121a(14) =125a(15) =162a(16) =211a(17) =215a(18) =216a(19) =254a(20) =461a(21) =465a(22) =511a(23) =512a(24) =515a(25) =516a(26) =642a(27) =665a(28) =1116a(29) =1121