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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 13 |
| 2 | 133 |
| 3 | 1333 |
| 4 | 13333 |
| 5 | 133333 |
| 6 | 1333333 |
| 7 | 125641 |
| 8 | 1256413 |
| 9 | 12564133 |
| 10 | 1197241 |
| 11 | 117481 |
| 12 | 9037 |
| 13 | 90391 |
| 14 | 9031 |
| 15 | 90313 |
| 16 | 903133 |
| 17 | 90241 |
| 18 | 902413 |
| 19 | 9024133 |
| 20 | 90241333 |
| 21 | 6941641 |
| 22 | 693241 |
| 23 | 6932413 |
| 24 | 69324133 |
| 25 | 6717241 |
| 26 | 671557 |
| 27 | 65557 |
| 28 | 5557 |
| 29 | 55591 |
| 30 | 5431 |
| 31 | 54313 |
| 32 | 543133 |
| 33 | 54241 |
[1,13,133,1333,13333,133333,1333333,125641, 1256413,12564133,1197241,117481,9037,90391,9031, 90313,903133,90241,902413,9024133,90241333, 6941641,693241,6932413,69324133,6717241,671557, 65557,5557,55591,5431,54313,543133,54241] |