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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 9 |
| 3 | 33 |
| 4 | 117 |
| 5 | 429 |
| 6 | 1577 |
| 7 | 5785 |
| 8 | 21217 |
| 9 | 77825 |
| 10 | 285473 |
| 11 | 1047145 |
| 12 | 3841029 |
| 13 | 14089277 |
| 14 | 51680881 |
| 15 | 189570641 |
| 16 | 695364065 |
| 17 | 2550664929 |
| 18 | 9356094041 |
| 19 | 34319088593 |
| 20 | 125885849013 |
| 21 | 461761883309 |
| 22 | 1693788766169 |
| 23 | 6212986580521 |
| 24 | 22789856102913 |
[1,9,33,117,429,1577,5785,21217,77825,285473, 1047145,3841029,14089277,51680881,189570641, 695364065,2550664929,9356094041,34319088593, 125885849013,461761883309,1693788766169, 6212986580521,22789856102913] |