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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 2 |
| 5 | 7 |
| 6 | 8 |
| 7 | 4 |
| 8 | 19 |
| 9 | 49 |
| 10 | 67 |
| 11 | 42 |
| 12 | 84 |
| 13 | 138 |
| 14 | 174 |
| 15 | 357 |
| 16 | 168 |
| 17 | 348 |
| 18 | 372 |
| 19 | 702 |
| 20 | 906 |
| 21 | 1407 |
[1,1,2,2,7,8,4,19,49,67,42,84,138,174,357,168,348, 372,702,906,1407] |