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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 9 |
| 4 | 29 |
| 5 | 99 |
| 6 | 348 |
| 7 | 1260 |
| 8 | 4644 |
| 9 | 17382 |
| 10 | 65822 |
| 11 | 251655 |
| 12 | 969819 |
| 13 | 3762517 |
| 14 | 14680890 |
| 15 | 57567228 |
| 16 | 226712655 |
| 17 | 896252850 |
| 18 | 3555116583 |
| 19 | 14144563158 |
[1,3,9,29,99,348,1260,4644,17382,65822,251655, 969819,3762517,14680890,57567228,226712655, 896252850,3555116583,14144563158] |