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| n | a(n) |
|---|---|
| 5 | 1 |
| 6 | 7 |
| 7 | 19 |
| 8 | 37 |
| 9 | 61 |
| 10 | 275 |
| 11 | 1793 |
| 12 | 9603 |
| 13 | 41441 |
| 14 | 206821 |
| 15 | 1678073 |
| 16 | 16665525 |
| 17 | 168175105 |
| 18 | 1702776291 |
| 19 | 20351416873 |
| 20 | 312390331791 |
[1,7,19,37,61,275,1793,9603,41441,206821,1678073, 16665525,168175105,1702776291,20351416873, 312390331791] |