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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 6 |
| 3 | 7 |
| 4 | 24 |
| 5 | 15 |
| 6 | 120 |
| 7 | 31 |
| 8 | 480 |
| 9 | 127 |
| 10 | 1920 |
| 11 | 511 |
| 12 | 7680 |
| 13 | 2047 |
| 14 | 32640 |
| 15 | 31231 |
| 16 | 105984 |
| 17 | 124927 |
| 18 | 423936 |
| 19 | 237567 |
| 20 | 2080768 |
| 21 | 425983 |
| 22 | 8355840 |
| 23 | 6356991 |
| 24 | 29327360 |
| 25 | 25296895 |
| 26 | 117309440 |
| 27 | 131334143 |
| 28 | 410517504 |
| 29 | 521142271 |
| 30 | 2145878016 |
| 31 | 28966911 |
| 32 | 8570929152 |
| 33 | 910688255 |
[1,1,6,7,24,15,120,31,480,127,1920,511,7680,2047, 32640,31231,105984,124927,423936,237567,2080768, 425983,8355840,6356991,29327360,25296895, 117309440,131334143,410517504,521142271, 2145878016,28966911,8570929152,910688255] |