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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 2 |
| 3 | 100 |
| 4 | 111 |
| 5 | 112 |
| 6 | 200 |
| 7 | 211 |
| 8 | 222 |
| 9 | 10000 |
| 10 | 10101 |
| 11 | 10102 |
| 12 | 11100 |
| 13 | 11111 |
| 14 | 11112 |
| 15 | 11200 |
| 16 | 11211 |
| 17 | 11222 |
| 18 | 20000 |
| 19 | 20101 |
| 20 | 20202 |
| 21 | 21100 |
| 22 | 21111 |
| 23 | 21212 |
| 24 | 22200 |
| 25 | 22211 |
| 26 | 22222 |
| 27 | 1000000 |
| 28 | 1001001 |
| 29 | 1001002 |
| 30 | 1010100 |
| 31 | 1010200 |
| 32 | 1011111 |
| 33 | 1011112 |
| 34 | 1011211 |
[0,1,2,100,111,112,200,211,222,10000,10101,10102, 11100,11111,11112,11200,11211,11222,20000,20101, 20202,21100,21111,21212,22200,22211,22222,1000000, 1001001,1001002,1010100,1010200,1011111,1011112, 1011211] |