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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 5 |
| 5 | 11 |
| 6 | 32 |
| 7 | 148 |
| 8 | 960 |
| 9 | 6802 |
| 10 | 58510 |
| 11 | 718772 |
| 12 | 11693848 |
| 13 | 239151220 |
| 14 | 6062327040 |
| 15 | 203215388485 |
[1,1,2,5,11,32,148,960,6802,58510,718772,11693848, 239151220,6062327040,203215388485] |