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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 3 |
| 3 | 5 |
| 4 | 7 |
| 5 | 13 |
| 6 | 17 |
| 7 | 31 |
| 8 | 71 |
| 9 | 113 |
| 10 | 131 |
| 11 | 211 |
| 12 | 311 |
| 13 | 1117 |
| 14 | 1151 |
| 15 | 1511 |
| 16 | 2111 |
| 17 | 11117 |
| 18 | 11171 |
| 19 | 131111 |
| 20 | 311111 |
| 21 | 511111 |
| 22 | 1111151 |
| 23 | 1111211 |
| 24 | 1111711 |
| 25 | 1117111 |
| 26 | 11111117 |
| 27 | 11111171 |
| 28 | 71111111 |
[2,3,5,7,13,17,31,71,113,131,211,311,1117,1151, 1511,2111,11117,11171,131111,311111,511111, 1111151,1111211,1111711,1117111,11111117,11111171, 71111111] |