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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 6 |
| 3 | 24 |
| 4 | 96 |
| 5 | 384 |
| 6 | 2304 |
| 7 | 9216 |
| 8 | 46080 |
| 9 | 276480 |
| 10 | 1658880 |
| 11 | 6635520 |
| 12 | 53084160 |
| 13 | 212336640 |
| 14 | 1274019840 |
| 15 | 10192158720 |
| 16 | 61152952320 |
| 17 | 244611809280 |
| 18 | 2201506283520 |
| 19 | 8806025134080 |
| 20 | 70448201072640 |
| 21 | 563585608581120 |
| 22 | 3381513651486720 |
| 23 | 13526054605946880 |
[2,6,24,96,384,2304,9216,46080,276480,1658880, 6635520,53084160,212336640,1274019840,10192158720, 61152952320,244611809280,2201506283520, 8806025134080,70448201072640,563585608581120, 3381513651486720,13526054605946880] |