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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 2 |
| 5 | 2 |
| 6 | 8 |
| 7 | 8 |
| 8 | 22 |
| 9 | 104 |
| 10 | 1128 |
| 11 | 1128 |
| 12 | 14520 |
| 13 | 14520 |
| 14 | 229734 |
| 15 | 3217088 |
[1,1,1,1,2,2,8,8,22,104,1128,1128,14520,14520, 229734,3217088] |