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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 19 |
| 2 | 253 |
| 3 | 3071 |
| 4 | 32633 |
| 5 | 313259 |
| 6 | 2787125 |
| 7 | 23120727 |
| 8 | 179773681 |
| 9 | 1318315075 |
| 10 | 9183188589 |
| 11 | 61157195951 |
| 12 | 390820296297 |
| 13 | 2405500230619 |
| 14 | 14298590156965 |
| 15 | 82219631208967 |
| 16 | 458093162029537 |
| 17 | 2477433774277747 |
| 18 | 13028767115904989 |
[1,19,253,3071,32633,313259,2787125,23120727, 179773681,1318315075,9183188589,61157195951, 390820296297,2405500230619,14298590156965, 82219631208967,458093162029537,2477433774277747, 13028767115904989] |