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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 7 |
| 4 | 49 |
| 5 | 501 |
| 6 | 6841 |
| 7 | 115123 |
| 8 | 2362305 |
| 9 | 57768553 |
| 10 | 1646192881 |
| 11 | 53952383871 |
| 12 | 2010872281969 |
| 13 | 84330050952733 |
| 14 | 3945169959883881 |
| 15 | 204416253047774251 |
| 16 | 11655594262050124801 |
| 17 | 727189793270478477777 |
| 18 | 49395902623624761264865 |
[1,1,1,7,49,501,6841,115123,2362305,57768553, 1646192881,53952383871,2010872281969, 84330050952733,3945169959883881, 204416253047774251,11655594262050124801, 727189793270478477777,49395902623624761264865] |