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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 7 |
| 3 | 15 |
| 4 | 35 |
| 5 | 83 |
| 6 | 205 |
| 7 | 521 |
| 8 | 1363 |
| 9 | 3651 |
| 10 | 9977 |
| 11 | 27701 |
| 12 | 77885 |
| 13 | 221133 |
| 14 | 632611 |
| 15 | 1820375 |
| 16 | 5262163 |
| 17 | 15266003 |
| 18 | 44414953 |
| 19 | 129521141 |
| 20 | 378427945 |
| 21 | 1107447881 |
| 22 | 3245329831 |
| 23 | 9521616731 |
| 24 | 27965113597 |
| 25 | 82210390733 |
| 26 | 241880335015 |
[1,3,7,15,35,83,205,521,1363,3651,9977,27701, 77885,221133,632611,1820375,5262163,15266003, 44414953,129521141,378427945,1107447881, 3245329831,9521616731,27965113597,82210390733, 241880335015] |