A039533 Numbers n such that representation in base 12 has same nonzero number of 4's and 7's.

55, 88, 199, 232, 343, 376, 487, 520, 583, 595, 607, 619, 643, 655, 660, 661, 662, 663, 665, 666, 668, 669, 670, 671, 679, 691, 703, 715, 775, 808, 919, 952, 1012, 1024, 1036, 1048, 1056, 1057, 1058, 1059, 1061, 1062, 1064, 1065, 1066, 1067