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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 4 |
| 5 | 8 |
| 6 | 16 |
| 7 | 192 |
| 8 | 3072 |
| 9 | 55296 |
| 10 | 110592 |
| 11 | 442368 |
| 12 | 13271040 |
| 13 | 477757440 |
| 14 | 19110297600 |
| 15 | 802632499200 |
| 16 | 1605264998400 |
| 17 | 6421059993600 |
| 18 | 12842119987200 |
| 19 | 770527199232000 |
| 20 | 50854795149312000 |
| 21 | 3559835660451840000 |
[1,1,1,4,8,16,192,3072,55296,110592,442368, 13271040,477757440,19110297600,802632499200, 1605264998400,6421059993600,12842119987200, 770527199232000,50854795149312000, 3559835660451840000] |