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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 6 |
| 3 | 3 |
| 4 | 28 |
| 5 | 7 |
| 6 | 120 |
| 7 | 111 |
| 8 | 432 |
| 9 | 223 |
| 10 | 1760 |
| 11 | 959 |
| 12 | 7872 |
| 13 | 4991 |
| 14 | 24448 |
| 15 | 20223 |
| 16 | 125696 |
| 17 | 77311 |
| 18 | 499200 |
| 19 | 523263 |
| 20 | 1207296 |
| 21 | 1783807 |
| 22 | 6420480 |
| 23 | 4124671 |
| 24 | 30846976 |
| 25 | 14344191 |
| 26 | 121495552 |
| 27 | 57655295 |
| 28 | 434290688 |
| 29 | 518750207 |
| 30 | 1316454400 |
| 31 | 1807679487 |
| 32 | 8251965440 |
| 33 | 1280180223 |
[1,1,6,3,28,7,120,111,432,223,1760,959,7872,4991, 24448,20223,125696,77311,499200,523263,1207296, 1783807,6420480,4124671,30846976,14344191, 121495552,57655295,434290688,518750207,1316454400, 1807679487,8251965440,1280180223] |