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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 70 |
| 4 | 4620 |
| 5 | 599256 |
| 6 | 128648520 |
| 7 | 41281606080 |
| 8 | 18507916627200 |
| 9 | 11049593741746560 |
| 10 | 8474451191616009600 |
| 11 | 8119493428719228192000 |
| 12 | 9504049395027168805824000 |
| 13 | 13345312208487981260926464000 |
| 14 | 22140681034117932250214874624000 |
| 15 | 42846437958647788197412779939840000 |
| 16 | 95657301566159892238019686222356480000 |
| 17 | 244038306493164073323605513327887380480000 |
[1,3,70,4620,599256,128648520,41281606080, 18507916627200,11049593741746560, 8474451191616009600,8119493428719228192000, 9504049395027168805824000, 13345312208487981260926464000, 22140681034117932250214874624000, 42846437958647788197412779939840000, 95657301566159892238019686222356480000, 244038306493164073323605513327887380480000] |