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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 5 |
| 4 | 16 |
| 5 | 58 |
| 6 | 231 |
| 7 | 1016 |
| 8 | 4782 |
| 9 | 23653 |
| 10 | 121727 |
| 11 | 648611 |
| 12 | 3541871 |
| 13 | 19713695 |
[1,2,5,16,58,231,1016,4782,23653,121727,648611, 3541871,19713695] |