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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 3 |
| 3 | 5 |
| 4 | 7 |
| 5 | 1117 |
| 6 | 1171 |
| 7 | 7331 |
| 8 | 131983991 |
| 9 | 179907191 |
| 10 | 179991179 |
| 11 | 191199311 |
| 12 | 191739971 |
| 13 | 191797919 |
| 14 | 199199311 |
| 15 | 199709971 |
| 16 | 199937971 |
| 17 | 337353739 |
| 18 | 373151113 |
| 19 | 733353337 |
| 20 | 797389337 |
| 21 | 919311739 |
| 22 | 971727179 |
| 23 | 1193100992213191 |
| 24 | 1193120192093911 |
| 25 | 1193123793413719 |
[2,3,5,7,1117,1171,7331,131983991,179907191, 179991179,191199311,191739971,191797919,199199311, 199709971,199937971,337353739,373151113,733353337, 797389337,919311739,971727179,1193100992213191, 1193120192093911,1193123793413719] |