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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 9 |
| 3 | 89 |
| 4 | 1265 |
| 5 | 22929 |
| 6 | 506809 |
| 7 | 13220521 |
| 8 | 397585761 |
| 9 | 13543386785 |
| 10 | 515418398441 |
| 11 | 21673889807481 |
| 12 | 998003450868049 |
| 13 | 49942515803293489 |
| 14 | 2698849517019693465 |
| 15 | 156631203355106962889 |
| 16 | 9716434375682706344129 |
| 17 | 641592631434102757993281 |
[1,1,9,89,1265,22929,506809,13220521,397585761, 13543386785,515418398441,21673889807481, 998003450868049,49942515803293489, 2698849517019693465,156631203355106962889, 9716434375682706344129,641592631434102757993281] |