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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 3 |
| 4 | 14 |
| 5 | 91 |
| 6 | 737 |
| 7 | 7096 |
| 8 | 78766 |
| 9 | 987842 |
| 10 | 13797282 |
| 11 | 212285511 |
| 12 | 3567147508 |
| 13 | 65001800879 |
| 14 | 1276876433466 |
| 15 | 26901212485406 |
| 16 | 605144725934525 |
| 17 | 14477882030623891 |
| 18 | 367106501841287465 |
| 19 | 9834718739970491625 |
[1,1,1,3,14,91,737,7096,78766,987842,13797282, 212285511,3567147508,65001800879,1276876433466, 26901212485406,605144725934525,14477882030623891, 367106501841287465,9834718739970491625] |