A136994 Numbers n such that n and the square of n use only the digits 1, 2, 4, 6 and 8.

1, 2, 4, 8, 11, 12, 21, 22, 41, 46, 68, 121, 122, 162, 168, 221, 261, 262, 642, 668, 1488, 4262, 6441, 6642, 6668, 8162, 8261, 11141, 11142, 14881, 66668, 81662, 121168, 148868, 248222, 248642, 664162, 664441, 666668, 684262, 828622, 1124662, 1188142, 1618222, 2118222, 2148122, 2148642, 4261668, 4628622, 6422182, 6644162, 6666668, 11142122