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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 5 |
| 4 | 84 |
| 5 | 6348 |
| 6 | 7743728 |
| 7 | 2414572893530 |
| 8 | 56130437190053299918162 |
[1,1,1,5,84,6348,7743728,2414572893530, 56130437190053299918162] |