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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 12 |
| 4 | 22 |
| 5 | 121 |
| 6 | 221 |
| 7 | 122 |
| 8 | 1211 |
| 9 | 2211 |
| 10 | 1221 |
| 11 | 1212 |
| 12 | 2212 |
| 13 | 1222 |
| 14 | 2222 |
| 15 | 12211 |
| 16 | 12121 |
| 17 | 22121 |
| 18 | 12221 |
| 19 | 22221 |
| 20 | 12212 |
| 21 | 12122 |
| 22 | 22122 |
| 23 | 12222 |
| 24 | 121211 |
| 25 | 221211 |
| 26 | 122211 |
| 27 | 222211 |
| 28 | 122121 |
| 29 | 121221 |
| 30 | 221221 |
| 31 | 122221 |
| 32 | 121212 |
| 33 | 221212 |
| 34 | 122212 |
| 35 | 222212 |
| 36 | 122122 |
| 37 | 121222 |
[1,2,12,22,121,221,122,1211,2211,1221,1212,2212, 1222,2222,12211,12121,22121,12221,22221,12212, 12122,22122,12222,121211,221211,122211,222211, 122121,121221,221221,122221,121212,221212,122212, 222212,122122,121222] |