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| n | a(n) |
|---|---|
| 2 | 1 |
| 3 | 5 |
| 4 | 26 |
| 5 | 247 |
| 6 | 2971 |
| 7 | 11729 |
| 8 | 17212 |
| 9 | 22396 |
| 10 | 30830 |
| 11 | 157265 |
| 12 | 210937 |
| 13 | 13364063 |
| 14 | 311800655 |
| 15 | 779670085 |
| 16 | 991056257 |
| 17 | 610968694 |
| 18 | 1532109175 |
| 19 | 13111582397 |
| 20 | 308183411213 |
| 21 | 374393615461 |
| 22 | 76437144605139 |
| 23 | 11567600813171033 |
| 24 | 3342011894016798 |
| 25 | 7482269384462067992 |
[1,5,26,247,2971,11729,17212,22396,30830,157265, 210937,13364063,311800655,779670085,991056257, 610968694,1532109175,13111582397,308183411213, 374393615461,76437144605139,11567600813171033, 3342011894016798,7482269384462067992] |