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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 0 |
| 4 | 1 |
| 5 | 1 |
| 6 | 2 |
| 7 | 1 |
| 8 | 4 |
| 9 | 1 |
| 10 | 10 |
| 11 | 3 |
| 12 | 37 |
| 13 | 32 |
| 14 | 340 |
| 15 | 1608 |
| 16 | 18020 |
| 17 | 193907 |
| 18 | 2867725 |
| 19 | 32674058 |
| 20 | 1581632114 |
| 21 | 6705889824 |
[1,1,1,0,1,1,2,1,4,1,10,3,37,32,340,1608,18020, 193907,2867725,32674058,1581632114,6705889824] |