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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 7 |
| 3 | 41 |
| 4 | 197 |
| 5 | 7025 |
| 6 | 68761 |
| 7 | 1663251 |
| 8 | 178945525 |
| 9 | 132150155017 |
| 10 | 16077043550231 |
| 11 | 4833128874789907 |
| 12 | 250487901809049775 |
| 13 | 6590569678028479808009 |
| 14 | 30288529373611329886681 |
| 15 | 111694000110134843095617996833 |
| 16 | 2161868815213291879136716036071 |
| 17 | 7842015457241561891262053489240216057 |
[1,7,41,197,7025,68761,1663251,178945525, 132150155017,16077043550231,4833128874789907, 250487901809049775,6590569678028479808009, 30288529373611329886681, 111694000110134843095617996833, 2161868815213291879136716036071, 7842015457241561891262053489240216057] |