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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 4 |
| 5 | 9 |
| 6 | 48 |
| 7 | 211 |
| 8 | 1736 |
| 9 | 9777 |
| 10 | 91169 |
| 11 | 739174 |
| 12 | 8613817 |
| 13 | 83763730 |
| 14 | 1105436491 |
| 15 | 13222076337 |
| 16 | 207852246589 |
| 17 | 2789691577561 |
| 18 | 47759515531854 |
| 19 | 755158220565169 |
| 20 | 14595210284816038 |
| 21 | 255814560447492788 |
| 22 | 5373613110108953192 |
| 23 | 105867623217924984398 |
| 24 | 2460702471446564481641 |
[1,1,1,4,9,48,211,1736,9777,91169,739174,8613817, 83763730,1105436491,13222076337,207852246589, 2789691577561,47759515531854,755158220565169, 14595210284816038,255814560447492788, 5373613110108953192,105867623217924984398, 2460702471446564481641] |