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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 11 |
| 3 | 212 |
| 4 | 2121 |
| 5 | 21211 |
| 6 | 121121 |
| 7 | 2212212 |
| 8 | 22122121 |
| 9 | 221221211 |
| 10 | 2212212112 |
| 11 | 22122121122 |
| 12 | 112212211211 |
| 13 | 1122122112112 |
| 14 | 11221221121121 |
| 15 | 112212211211212 |
| 16 | 1122122112112122 |
| 17 | 11211212212211211 |
| 18 | 112212211211212211 |
| 19 | 1211212212112212212 |
| 20 | 12112122121122122121 |
| 21 | 121121221211221221211 |
[2,11,212,2121,21211,121121,2212212,22122121, 221221211,2212212112,22122121122,112212211211, 1122122112112,11221221121121,112212211211212, 1122122112112122,11211212212211211, 112212211211212211,1211212212112212212, 12112122121122122121,121121221211221221211] |