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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 7 |
| 3 | 15 |
| 4 | 153 |
| 5 | 329 |
| 6 | 3359 |
| 7 | 7223 |
| 8 | 73745 |
| 9 | 158577 |
| 10 | 1619031 |
| 11 | 3481471 |
| 12 | 35544937 |
| 13 | 76433785 |
| 14 | 780369583 |
| 15 | 1678061799 |
| 16 | 17132585889 |
| 17 | 36840925793 |
| 18 | 376136519975 |
| 19 | 808822305647 |
| 20 | 8257870853561 |
| 21 | 17757249798441 |
| 22 | 181297022258367 |
| 23 | 389850673260055 |
| 24 | 3980276618830513 |
| 25 | 8558957561922769 |
[1,7,15,153,329,3359,7223,73745,158577,1619031, 3481471,35544937,76433785,780369583,1678061799, 17132585889,36840925793,376136519975,808822305647, 8257870853561,17757249798441,181297022258367, 389850673260055,3980276618830513,8558957561922769] |