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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 11 |
| 3 | 12 |
| 4 | 21 |
| 5 | 101 |
| 6 | 1001 |
| 7 | 1002 |
| 8 | 1011 |
| 9 | 10001 |
| 10 | 10002 |
| 11 | 10011 |
| 12 | 10012 |
| 13 | 10021 |
| 14 | 10101 |
| 15 | 11001 |
| 16 | 11002 |
| 17 | 100001 |
| 18 | 100002 |
| 19 | 100011 |
| 20 | 100012 |
| 21 | 100021 |
| 22 | 100101 |
| 23 | 101001 |
| 24 | 101002 |
| 25 | 101011 |
| 26 | 110001 |
| 27 | 110002 |
| 28 | 110011 |
| 29 | 110012 |
| 30 | 110021 |
| 31 | 110101 |
| 32 | 111001 |
| 33 | 111002 |
| 34 | 200001 |
[1,2,11,12,21,101,1001,1002,1011,10001,10002, 10011,10012,10021,10101,11001,11002,100001,100002, 100011,100012,100021,100101,101001,101002,101011, 110001,110002,110011,110012,110021,110101,111001, 111002,200001] |