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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 714 |
| 5 | 10101 |
| 6 | 67447 |
| 7 | 306569 |
| 8 | 1094959 |
| 9 | 3307802 |
| 10 | 8826810 |
| 11 | 21396106 |
| 12 | 48023760 |
| 13 | 101191247 |
| 14 | 202227753 |
| 15 | 386326083 |
[0,0,0,714,10101,67447,306569,1094959,3307802, 8826810,21396106,48023760,101191247,202227753, 386326083] |