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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 3 |
| 4 | 5 |
| 5 | 9 |
| 6 | 18 |
| 7 | 30 |
| 8 | 48 |
| 9 | 54 |
| 10 | 278 |
| 11 | 450 |
| 12 | 464 |
| 13 | 1425 |
| 14 | 1428 |
| 15 | 3029 |
| 16 | 7314 |
| 17 | 14273 |
| 18 | 15399 |
| 19 | 36962 |
| 20 | 50369 |
[1,2,3,5,9,18,30,48,54,278,450,464,1425,1428,3029, 7314,14273,15399,36962,50369] |