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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 4 |
| 3 | 12 |
| 4 | 48 |
| 5 | 240 |
| 6 | 240 |
| 7 | 1680 |
| 8 | 6720 |
| 9 | 20160 |
| 10 | 4032 |
| 11 | 44352 |
| 12 | 44352 |
| 13 | 576576 |
| 14 | 576576 |
| 15 | 2882880 |
| 16 | 11531520 |
| 17 | 196035840 |
| 18 | 196035840 |
| 19 | 3724680960 |
| 20 | 3724680960 |
| 21 | 3724680960 |
| 22 | 3724680960 |
| 23 | 85667662080 |
| 24 | 85667662080 |
| 25 | 428338310400 |
| 26 | 428338310400 |
[1,4,12,48,240,240,1680,6720,20160,4032,44352, 44352,576576,576576,2882880,11531520,196035840, 196035840,3724680960,3724680960,3724680960, 3724680960,85667662080,85667662080,428338310400, 428338310400] |