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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 0 |
| 5 | 0 |
| 6 | 0 |
| 7 | 0 |
| 8 | 0 |
| 9 | 0 |
| 10 | 0 |
| 11 | 0 |
| 12 | 0 |
| 13 | 0 |
| 14 | 0 |
| 15 | 0 |
| 16 | 1 |
| 17 | 0 |
| 18 | 2 |
| 19 | 2 |
| 20 | 15 |
| 21 | 35 |
| 22 | 247 |
| 23 | 1692 |
| 24 | 17409 |
| 25 | 197924 |
| 26 | 2492824 |
| 27 | 33117880 |
| 28 | 461597957 |
| 29 | 6709514218 |
| 30 | 101153412903 |
| 31 | 1597440868898 |
[0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,2,2,15,35, 247,1692,17409,197924,2492824,33117880,461597957, 6709514218,101153412903,1597440868898] |