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| n | a(n) |
|---|---|
| 1 | 3 |
| 2 | 7 |
| 3 | 19 |
| 4 | 53 |
| 5 | 147 |
| 6 | 401 |
| 7 | 1123 |
| 8 | 3137 |
| 9 | 8793 |
| 10 | 24599 |
| 11 | 69287 |
| 12 | 194967 |
| 13 | 550361 |
| 14 | 1552645 |
| 15 | 4393021 |
| 16 | 12425121 |
| 17 | 35213027 |
| 18 | 99771855 |
| 19 | 283162701 |
| 20 | 803538483 |
| 21 | 2283184527 |
| 22 | 6486977223 |
| 23 | 18450767769 |
| 24 | 52477038631 |
| 25 | 149387309235 |
| 26 | 425257329235 |
| 27 | 1211493474199 |
[3,7,19,53,147,401,1123,3137,8793,24599,69287, 194967,550361,1552645,4393021,12425121,35213027, 99771855,283162701,803538483,2283184527, 6486977223,18450767769,52477038631,149387309235, 425257329235,1211493474199] |