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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 5 |
| 4 | 7 |
| 5 | 15 |
| 6 | 25 |
| 7 | 80 |
| 8 | 321 |
| 9 | 401 |
| 10 | 1105 |
| 11 | 1440 |
| 12 | 2185 |
| 13 | 17665 |
| 14 | 26585 |
| 15 | 132920 |
| 16 | 287216 |
| 17 | 659355 |
| 18 | 1267785 |
| 19 | 2096240 |
| 20 | 3612505 |
[1,3,5,7,15,25,80,321,401,1105,1440,2185,17665, 26585,132920,287216,659355,1267785,2096240, 3612505] |