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| n | a(n) |
|---|---|
| 5 | 1 |
| 6 | 57 |
| 7 | 1191 |
| 8 | 15619 |
| 9 | 156190 |
| 10 | 1310354 |
| 11 | 9738114 |
| 12 | 66318474 |
| 13 | 423281535 |
| 14 | 2571742175 |
| 15 | 15041229521 |
| 16 | 85383238549 |
| 17 | 473353301060 |
| 18 | 2575022097600 |
| 19 | 13796160184500 |
| 20 | 73008517581444 |
| 21 | 382493246941965 |
| 22 | 1987497491971605 |
| 23 | 10258045633638475 |
[1,57,1191,15619,156190,1310354,9738114,66318474, 423281535,2571742175,15041229521,85383238549, 473353301060,2575022097600,13796160184500, 73008517581444,382493246941965,1987497491971605, 10258045633638475] |