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| n | a(n) |
|---|---|
| 2 | 1 |
| 3 | 1 |
| 4 | 5 |
| 5 | 41 |
| 6 | 438 |
| 7 | 5564 |
| 8 | 80237 |
| 9 | 1278297 |
| 10 | 22108374 |
| 11 | 410124999 |
| 12 | 8089569676 |
| 13 | 168555880750 |
| 14 | 3691281132962 |
| 15 | 84623035267642 |
| 16 | 2024303994864497 |
| 17 | 50394612947711173 |
| 18 | 1302706707186206332 |
| 19 | 34901118404682549804 |
| 20 | 967494986526757083191 |
| 21 | 27710705833750559374772 |
| 22 | 818986747695251513692537 |
[1,1,5,41,438,5564,80237,1278297,22108374, 410124999,8089569676,168555880750,3691281132962, 84623035267642,2024303994864497,50394612947711173, 1302706707186206332,34901118404682549804, 967494986526757083191,27710705833750559374772, 818986747695251513692537] |