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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 15 |
| 4 | 63 |
| 5 | 267 |
| 6 | 1107 |
| 7 | 4623 |
| 8 | 19071 |
| 9 | 78987 |
| 10 | 324543 |
| 11 | 1337511 |
| 12 | 5483235 |
| 13 | 22527315 |
| 14 | 92200455 |
| 15 | 377965479 |
| 16 | 1544925891 |
| 17 | 6322891707 |
[1,3,15,63,267,1107,4623,19071,78987,324543, 1337511,5483235,22527315,92200455,377965479, 1544925891,6322891707] |