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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 15 |
| 3 | 159 |
| 4 | 2191 |
| 5 | 31168 |
| 6 | 447343 |
| 7 | 6427791 |
| 8 | 92387812 |
| 9 | 1327953799 |
| 10 | 19087798375 |
| 11 | 274365294336 |
| 12 | 3943689122935 |
| 13 | 56686048473223 |
| 14 | 814797524429284 |
| 15 | 11711788424726319 |
| 16 | 168343648648695295 |
| 17 | 2419748633865949120 |
[2,15,159,2191,31168,447343,6427791,92387812, 1327953799,19087798375,274365294336,3943689122935, 56686048473223,814797524429284,11711788424726319, 168343648648695295,2419748633865949120] |