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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 2 |
| 5 | 1 |
| 6 | 1648 |
| 7 | 10916 |
| 8 | 227056 |
| 9 | 17 |
| 10 | 37138 |
| 11 | 32596907 |
| 12 | 203911047902268383 |
| 13 | 61 |
[1,1,1,2,1,1648,10916,227056,17,37138,32596907, 203911047902268383,61] |