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| n | a(n) |
|---|---|
| 3 | 0 |
| 4 | 1 |
| 5 | 1 |
| 6 | 1 |
| 7 | 1 |
| 8 | 12 |
| 9 | 21 |
| 10 | 74 |
| 11 | 309 |
| 12 | 1376 |
| 13 | 5016 |
| 14 | 27198 |
| 15 | 138592 |
| 16 | 928544 |
| 17 | 4735266 |
| 18 | 31263708 |
| 19 | 206761952 |
| 20 | 1677199872 |
| 21 | 11111483094 |
[0,1,1,1,1,12,21,74,309,1376,5016,27198,138592, 928544,4735266,31263708,206761952,1677199872, 11111483094] |