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| n | a(n) |
|---|---|
| 1 | 13 |
| 2 | 161 |
| 3 | 606 |
| 4 | 6433 |
| 5 | 39916 |
| 6 | 341011 |
| 7 | 2399000 |
| 8 | 18334295 |
| 9 | 130350889 |
| 10 | 947356115 |
| 11 | 6693133584 |
| 12 | 47588393713 |
| 13 | 334543874696 |
| 14 | 2356688545513 |
| 15 | 16526137384381 |
| 16 | 115977271626785 |
| 17 | 812415242570854 |
| 18 | 5692700008978435 |
| 19 | 39860063264311589 |
[13,161,606,6433,39916,341011,2399000,18334295, 130350889,947356115,6693133584,47588393713, 334543874696,2356688545513,16526137384381, 115977271626785,812415242570854,5692700008978435, 39860063264311589] |