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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 5 |
| 2 | 21 |
| 3 | 85 |
| 4 | 413 |
| 5 | 1765 |
| 6 | 7325 |
| 7 | 30085 |
| 8 | 122813 |
| 9 | 499045 |
| 10 | 2020445 |
| 11 | 8156485 |
| 12 | 32854013 |
| 13 | 132108325 |
| 14 | 530526365 |
| 15 | 2128417285 |
[1,5,21,85,413,1765,7325,30085,122813,499045, 2020445,8156485,32854013,132108325,530526365, 2128417285] |