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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 22 |
| 4 | 87 |
| 5 | 1726 |
| 6 | 68819 |
| 7 | 4003781 |
| 8 | 565032173 |
| 9 | 152764693020 |
| 10 | 80175405643606 |
[1,1,22,87,1726,68819,4003781,565032173, 152764693020,80175405643606] |