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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 11 |
| 4 | 12 |
| 5 | 21 |
| 6 | 22 |
| 7 | 112 |
| 8 | 121 |
| 9 | 122 |
| 10 | 211 |
| 11 | 212 |
| 12 | 221 |
| 13 | 1121 |
| 14 | 1122 |
| 15 | 1211 |
| 16 | 1212 |
| 17 | 1221 |
| 18 | 2112 |
| 19 | 2121 |
| 20 | 2122 |
| 21 | 2211 |
| 22 | 2212 |
| 23 | 11211 |
| 24 | 11212 |
| 25 | 11221 |
| 26 | 12112 |
| 27 | 12122 |
| 28 | 12211 |
| 29 | 12212 |
| 30 | 21121 |
| 31 | 21122 |
| 32 | 21211 |
| 33 | 21221 |
| 34 | 22112 |
| 35 | 22121 |
| 36 | 22122 |
| 37 | 112112 |
| 38 | 112122 |
| 39 | 112212 |
| 40 | 121121 |
| 41 | 121122 |
| 42 | 121221 |
[1,2,11,12,21,22,112,121,122,211,212,221,1121, 1122,1211,1212,1221,2112,2121,2122,2211,2212, 11211,11212,11221,12112,12122,12211,12212,21121, 21122,21211,21221,22112,22121,22122,112112,112122, 112212,121121,121122,121221] |