A037305 (sum of base 2 digits of n)=(sum of base 7 digits of n).

1, 21, 58, 59, 106, 107, 126, 127, 154, 155, 203, 246, 247, 252, 253, 366, 367, 378, 379, 394, 395, 414, 415, 444, 445, 462, 463, 492, 493, 498, 499, 504, 505, 539, 637, 688, 689, 707, 736, 737, 756, 757, 798, 799, 847, 882, 883