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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 2 |
| 5 | 2 |
| 6 | 12 |
| 7 | 12 |
| 8 | 48 |
| 9 | 144 |
| 10 | 1440 |
| 11 | 1440 |
| 12 | 34560 |
| 13 | 34560 |
| 14 | 483840 |
| 15 | 7257600 |
| 16 | 58060800 |
| 17 | 58060800 |
| 18 | 3135283200 |
| 19 | 3135283200 |
| 20 | 125411328000 |
| 21 | 2633637888000 |
| 22 | 57940033536000 |
| 23 | 57940033536000 |
| 24 | 5562243219456000 |
| 25 | 27811216097280000 |
| 26 | 723091618529280000 |
| 27 | 6507824566763520000 |
[1,1,1,1,2,2,12,12,48,144,1440,1440,34560,34560, 483840,7257600,58060800,58060800,3135283200, 3135283200,125411328000,2633637888000, 57940033536000,57940033536000,5562243219456000, 27811216097280000,723091618529280000, 6507824566763520000] |