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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 4 |
| 3 | 8 |
| 4 | 88 |
| 5 | 252 |
| 6 | 2112 |
| 7 | 2112 |
| 8 | 2112 |
| 9 | 4224 |
| 10 | 8448 |
| 11 | 48384 |
| 12 | 48384 |
| 13 | 405504 |
| 14 | 405504 |
| 15 | 405504 |
| 16 | 40955904 |
| 17 | 677707776 |
| 18 | 677707776 |
| 19 | 677707776 |
| 20 | 677707776 |
| 21 | 677574475776 |
| 22 | 677574475776 |
| 23 | 42833977933824 |
| 24 | 6929958668599296 |
[2,4,8,88,252,2112,2112,2112,4224,8448,48384, 48384,405504,405504,405504,40955904,677707776, 677707776,677707776,677707776,677574475776, 677574475776,42833977933824,6929958668599296] |