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| n | a(n) |
|---|---|
| 17 | 0 |
| 18 | 0 |
| 19 | 1 |
| 20 | 1 |
| 21 | 2 |
| 22 | 9 |
| 23 | 6 |
| 24 | 23 |
| 25 | 21 |
| 26 | 42 |
| 27 | 69 |
| 28 | 87 |
| 29 | 155 |
| 30 | 206 |
| 31 | 297 |
| 32 | 436 |
| 33 | 507 |
| 34 | 892 |
| 35 | 967 |
| 36 | 1612 |
| 37 | 1865 |
[0,0,1,1,2,9,6,23,21,42,69,87,155,206,297,436,507, 892,967,1612,1865] |