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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 6 |
| 3 | 120 |
| 4 | 10368 |
| 5 | 2582208 |
| 6 | 3143720448 |
| 7 | 11692182896640 |
| 8 | 219197554267521024 |
| 9 | 12804488375721592356864 |
| 10 | 3325324798296500862330077184 |
| 11 | 2537067900325971750395878897090560 |
| 12 | 8900626797123384385697033838119859781632 |
| 13 | 65799342288255766009804607851267459830106816512 |
[1,6,120,10368,2582208,3143720448,11692182896640, 219197554267521024,12804488375721592356864, 3325324798296500862330077184, 2537067900325971750395878897090560, 8900626797123384385697033838119859781632, 65799342288255766009804607851267459830106816512] |