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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 23 |
| 4 | 223 |
| 5 | 233 |
| 6 | 237 |
| 7 | 2237 |
| 8 | 2337 |
| 9 | 22337 |
| 10 | 23137 |
| 11 | 23337 |
| 12 | 23373 |
| 13 | 23797 |
| 14 | 223373 |
| 15 | 223797 |
| 16 | 231373 |
| 17 | 233137 |
| 18 | 233797 |
| 19 | 2233797 |
| 20 | 2313797 |
| 21 | 2331373 |
| 22 | 2333797 |
| 23 | 2337379 |
| 24 | 2337397 |
| 25 | 2353797 |
| 26 | 22353797 |
| 27 | 22373797 |
| 28 | 23137397 |
| 29 | 23173797 |
| 30 | 23313797 |
| 31 | 23353797 |
| 32 | 23373797 |
[1,2,23,223,233,237,2237,2337,22337,23137,23337, 23373,23797,223373,223797,231373,233137,233797, 2233797,2313797,2331373,2333797,2337379,2337397, 2353797,22353797,22373797,23137397,23173797, 23313797,23353797,23373797] |