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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 4 |
| 3 | 12 |
| 4 | 16 |
| 5 | 48 |
| 6 | 144 |
| 7 | 720 |
| 8 | 1296 |
| 9 | 6480 |
| 10 | 32400 |
| 11 | 184320 |
| 12 | 331776 |
| 13 | 1658880 |
| 14 | 8294400 |
| 15 | 58060800 |
| 16 | 65536 |
| 17 | 196608 |
| 18 | 589824 |
| 19 | 2949120 |
| 20 | 5308416 |
| 21 | 26542080 |
| 22 | 132710400 |
| 23 | 928972800 |
| 24 | 3317760000 |
| 25 | 23224320000 |
| 26 | 162570240000 |
| 27 | 1788272640000 |
| 28 | 7965941760000 |
| 29 | 87625359360000 |
[1,2,4,12,16,48,144,720,1296,6480,32400,184320, 331776,1658880,8294400,58060800,65536,196608, 589824,2949120,5308416,26542080,132710400, 928972800,3317760000,23224320000,162570240000, 1788272640000,7965941760000,87625359360000] |