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| n | a(n) |
|---|---|
| 1 | 313 |
| 2 | 757 |
| 3 | 131113 |
| 4 | 171517 |
| 5 | 312931 |
| 6 | 393739 |
| 7 | 474547 |
| 8 | 494749 |
| 9 | 575557 |
| 10 | 939193 |
| 11 | 111109111 |
| 12 | 127125127 |
| 13 | 139137139 |
| 14 | 147145147 |
| 15 | 151149151 |
| 16 | 169167169 |
| 17 | 189187189 |
| 18 | 213211213 |
| 19 | 217215217 |
| 20 | 227225227 |
| 21 | 237235237 |
| 22 | 239237239 |
| 23 | 247245247 |
| 24 | 253251253 |
| 25 | 269267269 |
| 26 | 331329331 |
| 27 | 333331333 |
| 28 | 353351353 |
| 29 | 363361363 |
| 30 | 377375377 |
| 31 | 387385387 |
| 32 | 389387389 |
| 33 | 393391393 |
[313,757,131113,171517,312931,393739,474547, 494749,575557,939193,111109111,127125127, 139137139,147145147,151149151,169167169,189187189, 213211213,217215217,227225227,237235237,239237239, 247245247,253251253,269267269,331329331,333331333, 353351353,363361363,377375377,387385387,389387389, 393391393] |