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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 3 |
| 5 | 7 |
| 6 | 16 |
| 7 | 65 |
| 8 | 321 |
| 9 | 4546 |
| 10 | 107587 |
| 11 | 20773703 |
| 12 | 11595736272 |
| 13 | 431558332068481 |
| 14 | 134461531248108526465 |
| 15 | 186242594112190847520182173826 |
| 16 | 18079903385772308300945867582153787570051 |
| 17 | 34686303861638264961101080464895364211215702792496667048327 |
[0,1,1,2,3,7,16,65,321,4546,107587,20773703, 11595736272,431558332068481,134461531248108526465, 186242594112190847520182173826, 18079903385772308300945867582153787570051, 34686303861638264961101080464895364211215702792496\ 667048327] |