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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 5 |
| 5 | 13 |
| 6 | 55 |
| 7 | 233 |
| 8 | 1597 |
| 9 | 10946 |
| 10 | 75025 |
| 11 | 514229 |
| 12 | 3524578 |
| 13 | 39088169 |
| 14 | 433494437 |
| 15 | 4807526976 |
| 16 | 53316291173 |
| 17 | 591286729879 |
| 18 | 6557470319842 |
| 19 | 117669030460994 |
| 20 | 2111485077978050 |
| 21 | 37889062373143906 |
| 22 | 679891637638612258 |
[1,1,2,5,13,55,233,1597,10946,75025,514229, 3524578,39088169,433494437,4807526976,53316291173, 591286729879,6557470319842,117669030460994, 2111485077978050,37889062373143906, 679891637638612258] |