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| n | a(n) |
|---|---|
| 1 | 3 |
| 2 | 2 |
| 3 | 1 |
| 4 | 8 |
| 5 | 90 |
| 6 | 168 |
| 7 | 9352 |
| 8 | 46189 |
| 9 | 2515371 |
| 10 | 721970 |
| 11 | 6449639 |
| 12 | 565062156 |
| 13 | 11336460025 |
| 14 | 37151747513 |
| 15 | 256994754033 |
[3,2,1,8,90,168,9352,46189,2515371,721970,6449639, 565062156,11336460025,37151747513,256994754033] |