Numbers k such that k and k^2 use only the digits 3, 6, 7, 8 and 9.

Terms

a(0) =3a(1) =6a(2) =63a(3) =83a(4) =86a(5) =833a(6) =836a(7) =876a(8) =883a(9) =887a(10) =937a(11) =8363a(12) =8876a(13) =8887a(14) =8937a(15) =9687a(16) =9833a(17) =9883a(18) =79836a(19) =79867a(20) =93637a(21) =96633a(22) =96886a(23) =98333a(24) =98336a(25) =98376a(26) =98887a(27) =798367a(28) =798667a(29) =936876