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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 3 |
| 3 | 13 |
| 4 | 13 |
| 5 | 491 |
| 6 | 1851 |
| 7 | 12721 |
| 8 | 12721 |
| 9 | 109453 |
| 10 | 586951 |
| 11 | 120797465 |
| 12 | 624141002 |
| 13 | 4044619541 |
| 14 | 267793490438 |
| 15 | 315400191511 |
| 16 | 1285600699441 |
[2,3,13,13,491,1851,12721,12721,109453,586951, 120797465,624141002,4044619541,267793490438, 315400191511,1285600699441] |