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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 4 |
| 3 | 6 |
| 4 | 48 |
| 5 | 30 |
| 6 | 1152 |
| 7 | 266 |
| 8 | 45824 |
| 9 | 4050 |
| 10 | 2736000 |
| 11 | 75702 |
| 12 | 233017344 |
| 13 | 2060734 |
[2,4,6,48,30,1152,266,45824,4050,2736000,75702, 233017344,2060734] |