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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 3 |
| 4 | 7 |
| 5 | 13 |
| 6 | 33 |
| 7 | 79 |
| 8 | 229 |
| 9 | 671 |
| 10 | 2179 |
| 11 | 7283 |
| 12 | 25632 |
| 13 | 92427 |
| 14 | 342676 |
| 15 | 1293482 |
| 16 | 4966625 |
| 17 | 19322745 |
| 18 | 76069927 |
[1,2,3,7,13,33,79,229,671,2179,7283,25632,92427, 342676,1293482,4966625,19322745,76069927] |