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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 3 |
| 4 | 8 |
| 5 | 27 |
| 6 | 78 |
| 7 | 219 |
| 8 | 649 |
| 9 | 1805 |
| 10 | 4987 |
| 11 | 13179 |
| 12 | 34331 |
| 13 | 87203 |
| 14 | 217281 |
| 15 | 532073 |
| 16 | 1278041 |
| 17 | 3025466 |
| 18 | 7046194 |
| 19 | 16192534 |
| 20 | 36706373 |
| 21 | 82197783 |
| 22 | 181900279 |
| 23 | 398099637 |
| 24 | 862217855 |
| 25 | 1848842707 |
| 26 | 3927404946 |
| 27 | 8267742253 |
| 28 | 17257223344 |
| 29 | 35726693834 |
[1,2,3,8,27,78,219,649,1805,4987,13179,34331, 87203,217281,532073,1278041,3025466,7046194, 16192534,36706373,82197783,181900279,398099637, 862217855,1848842707,3927404946,8267742253, 17257223344,35726693834] |