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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 3 |
| 4 | 5 |
| 5 | 17 |
| 6 | 53 |
| 7 | 260 |
| 8 | 1466 |
| 9 | 10915 |
| 10 | 93196 |
| 11 | 917898 |
| 12 | 10015299 |
| 13 | 119914982 |
| 14 | 1557364352 |
| 15 | 21797494987 |
| 16 | 326930305166 |
| 17 | 5230756117008 |
| 18 | 88922108947567 |
| 19 | 1600594738591550 |
| 20 | 30411281088326498 |
| 21 | 608225534389576956 |
| 22 | 12772735698577492558 |
[1,1,3,5,17,53,260,1466,10915,93196,917898, 10015299,119914982,1557364352,21797494987, 326930305166,5230756117008,88922108947567, 1600594738591550,30411281088326498, 608225534389576956,12772735698577492558] |