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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 10 |
| 4 | 20 |
| 5 | 100 |
| 6 | 101 |
| 7 | 200 |
| 8 | 201 |
| 9 | 1000 |
| 10 | 1001 |
| 11 | 1002 |
| 12 | 1010 |
| 13 | 2000 |
| 14 | 2001 |
| 15 | 2002 |
| 16 | 2010 |
| 17 | 10000 |
| 18 | 10001 |
| 19 | 10002 |
| 20 | 10010 |
| 21 | 10020 |
| 22 | 10100 |
| 23 | 10101 |
| 24 | 20000 |
| 25 | 20001 |
| 26 | 20002 |
| 27 | 20010 |
| 28 | 20020 |
| 29 | 20100 |
| 30 | 20101 |
| 31 | 100000 |
| 32 | 100001 |
| 33 | 100002 |
| 34 | 100010 |
| 35 | 100020 |
| 36 | 100100 |
| 37 | 100101 |
| 38 | 100200 |
| 39 | 100201 |
[1,2,10,20,100,101,200,201,1000,1001,1002,1010, 2000,2001,2002,2010,10000,10001,10002,10010,10020, 10100,10101,20000,20001,20002,20010,20020,20100, 20101,100000,100001,100002,100010,100020,100100, 100101,100200,100201] |