A085186 Sequence A085195 shown in base 4.
0, 1, 10, 11, 13, 100, 101, 110, 111, 113, 130, 131, 133, 203, 1000, 1001, 1010, 1011, 1013, 1100, 1101, 1110, 1111, 1113, 1130, 1131, 1133, 1203, 1300, 1301, 1310, 1311, 1313, 1330, 1331, 1333, 2003, 2030, 2031, 2033, 2103, 2123, 10000, 10001, 10010
Offset: 0