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| n | a(n) |
|---|---|
| 1 | 3 |
| 2 | 31 |
| 3 | 311 |
| 4 | 3119 |
| 5 | 31193 |
| 6 | 3119317 |
| 7 | 31193171 |
| 8 | 311931713 |
| 9 | 3119317139 |
| 10 | 311931713939 |
| 11 | 31193171393933 |
| 12 | 3119317139393353 |
| 13 | 31193171393933531 |
| 14 | 3119317139393353121 |
| 15 | 311931713939335312127 |
| 16 | 311931713939335312127113 |
| 17 | 31193171393933531212711399 |
| 18 | 31193171393933531212711399123 |
[3,31,311,3119,31193,3119317,31193171,311931713, 3119317139,311931713939,31193171393933, 3119317139393353,31193171393933531, 3119317139393353121,311931713939335312127, 311931713939335312127113, 31193171393933531212711399, 31193171393933531212711399123] |