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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 4 |
| 3 | 11 |
| 4 | 17 |
| 5 | 45 |
| 6 | 75 |
| 7 | 195 |
| 8 | 339 |
| 9 | 873 |
| 10 | 1558 |
| 11 | 3989 |
| 12 | 7247 |
| 13 | 18483 |
| 14 | 34016 |
| 15 | 86515 |
| 16 | 160795 |
| 17 | 408105 |
| 18 | 764388 |
| 19 | 1936881 |
| 20 | 3650571 |
| 21 | 9238023 |
| 22 | 17501619 |
| 23 | 44241261 |
| 24 | 84179877 |
| 25 | 212601015 |
| 26 | 406020930 |
| 27 | 1024642875 |
| 28 | 1963073865 |
| 29 | 4950790605 |
[1,3,4,11,17,45,75,195,339,873,1558,3989,7247, 18483,34016,86515,160795,408105,764388,1936881, 3650571,9238023,17501619,44241261,84179877, 212601015,406020930,1024642875,1963073865, 4950790605] |