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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 7 |
| 4 | 13 |
| 5 | 21 |
| 6 | 31 |
| 7 | 48 |
| 8 | 57 |
| 9 | 73 |
| 10 | 91 |
| 11 | 120 |
| 12 | 133 |
| 13 | 168 |
| 14 | 183 |
| 15 | 255 |
| 16 | 255 |
| 17 | 273 |
| 18 | 307 |
[1,3,7,13,21,31,48,57,73,91,120,133,168,183,255, 255,273,307] |