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| n | a(n) |
|---|---|
| 1 | 12 |
| 2 | 32 |
| 3 | 168 |
| 4 | 1152 |
| 5 | 9600 |
| 6 | 97920 |
| 7 | 1491840 |
| 8 | 21127680 |
| 9 | 377395200 |
| 10 | 7605964800 |
| 11 | 164457216000 |
| 12 | 3935477145600 |
| 13 | 102571486617600 |
| 14 | 2858053098700800 |
| 15 | 85725900868608000 |
| 16 | 2745404797943808000 |
| 17 | 93266934645620736000 |
| 18 | 3356738924418367488000 |
| 19 | 127589166595209166848000 |
[12,32,168,1152,9600,97920,1491840,21127680, 377395200,7605964800,164457216000,3935477145600, 102571486617600,2858053098700800, 85725900868608000,2745404797943808000, 93266934645620736000,3356738924418367488000, 127589166595209166848000] |