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| n | a(n) |
|---|---|
| 0 | -1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 11 |
| 4 | 31 |
| 5 | 87 |
| 6 | 239 |
| 7 | 655 |
| 8 | 1791 |
| 9 | 4895 |
| 10 | 13375 |
| 11 | 36543 |
| 12 | 99839 |
| 13 | 272767 |
| 14 | 745215 |
| 15 | 2035967 |
| 16 | 5562367 |
| 17 | 15196671 |
| 18 | 41518079 |
| 19 | 113429503 |
| 20 | 309895167 |
| 21 | 846649343 |
| 22 | 2313089023 |
| 23 | 6319476735 |
| 24 | 17265131519 |
| 25 | 47169216511 |
| 26 | 128868696063 |
| 27 | 352075825151 |
| 28 | 961889042431 |
| 29 | 2627929735167 |
| 30 | 7179637555199 |
[-1,1,3,11,31,87,239,655,1791,4895,13375,36543, 99839,272767,745215,2035967,5562367,15196671, 41518079,113429503,309895167,846649343,2313089023, 6319476735,17265131519,47169216511,128868696063, 352075825151,961889042431,2627929735167, 7179637555199] |