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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 2 |
| 5 | 2 |
| 6 | 3 |
| 7 | 5 |
| 8 | 8 |
| 9 | 11 |
| 10 | 18 |
| 11 | 29 |
| 12 | 49 |
| 13 | 83 |
| 14 | 148 |
| 15 | 267 |
| 16 | 507 |
| 17 | 977 |
| 18 | 1958 |
| 19 | 4041 |
| 20 | 8626 |
| 21 | 18942 |
[1,1,1,2,2,3,5,8,11,18,29,49,83,148,267,507,977, 1958,4041,8626,18942] |