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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 9 |
| 4 | 39 |
| 5 | 197 |
| 6 | 1187 |
| 7 | 8309 |
| 8 | 66476 |
| 9 | 598287 |
| 10 | 5982879 |
| 11 | 65811677 |
| 12 | 789740126 |
| 13 | 10266621646 |
| 14 | 143732703044 |
| 15 | 2155990545670 |
| 16 | 34495848730735 |
| 17 | 586429428422497 |
| 18 | 10555729711604956 |
| 19 | 200558864520494172 |
| 20 | 4011177290409883459 |
[1,3,9,39,197,1187,8309,66476,598287,5982879, 65811677,789740126,10266621646,143732703044, 2155990545670,34495848730735,586429428422497, 10555729711604956,200558864520494172, 4011177290409883459] |