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| n | a(n) |
|---|---|
| 7 | 1 |
| 8 | 1 |
| 9 | 4 |
| 10 | 21 |
| 11 | 266 |
| 12 | 7848 |
| 13 | 1 |
| 14 | 367860 |
| 15 | 0 |
| 16 | 21609299 |
| 17 | 1 |
| 18 | 1470293674 |
| 19 | 1 |
| 20 | 113314233799 |
| 21 | 9 |
| 22 | 9799685588930 |
| 23 | 6 |
[1,1,4,21,266,7848,1,367860,0,21609299,1, 1470293674,1,113314233799,9,9799685588930,6] |