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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 8 |
| 3 | 24 |
| 4 | 120 |
| 5 | 840 |
| 6 | 9240 |
| 7 | 120120 |
| 8 | 2042040 |
| 9 | 38798760 |
| 10 | 892371480 |
| 11 | 25878772920 |
| 12 | 802241960520 |
| 13 | 29682952539240 |
| 14 | 1217001054108840 |
| 15 | 52331045326680120 |
| 16 | 2459559130353965640 |
| 17 | 130356633908760178920 |
| 18 | 7691041400616850556280 |
| 19 | 469153525437627883933080 |
| 20 | 31433286204321068223516360 |
[2,8,24,120,840,9240,120120,2042040,38798760, 892371480,25878772920,802241960520,29682952539240, 1217001054108840,52331045326680120, 2459559130353965640,130356633908760178920, 7691041400616850556280,469153525437627883933080, 31433286204321068223516360] |