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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 1 |
| 6 | 3 |
| 7 | 9 |
| 8 | 19 |
| 9 | 52 |
| 10 | 181 |
| 11 | 742 |
| 12 | 4149 |
| 13 | 26078 |
| 14 | 174469 |
| 15 | 1396213 |
| 16 | 13529455 |
[1,1,1,1,1,3,9,19,52,181,742,4149,26078,174469, 1396213,13529455] |