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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 9 |
| 4 | 19 |
| 5 | 49 |
| 6 | 123 |
| 7 | 297 |
| 8 | 739 |
| 9 | 1825 |
| 10 | 4491 |
| 11 | 11097 |
| 12 | 27379 |
| 13 | 67537 |
| 14 | 166683 |
| 15 | 411273 |
| 16 | 1014787 |
| 17 | 2504065 |
| 18 | 6178731 |
| 19 | 15246009 |
| 20 | 37619731 |
| 21 | 92826673 |
| 22 | 229050171 |
| 23 | 565182441 |
| 24 | 1394589475 |
| 25 | 3441155041 |
| 26 | 8491063755 |
| 27 | 20951731737 |
| 28 | 51698479411 |
| 29 | 127566197905 |
| 30 | 314770083675 |
[1,3,9,19,49,123,297,739,1825,4491,11097,27379, 67537,166683,411273,1014787,2504065,6178731, 15246009,37619731,92826673,229050171,565182441, 1394589475,3441155041,8491063755,20951731737, 51698479411,127566197905,314770083675] |