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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | -1 |
| 2 | -1 |
| 3 | 29 |
| 4 | 275 |
| 5 | 1829 |
| 6 | 10739 |
| 7 | 59429 |
| 8 | 318275 |
| 9 | 1670789 |
| 10 | 8656979 |
| 11 | 44454629 |
| 12 | 226827875 |
| 13 | 1151991749 |
| 14 | 5830280819 |
| 15 | 29429454629 |
| 16 | 148249811075 |
| 17 | 745630312709 |
| 18 | 3745590106259 |
| 19 | 18797445635429 |
| 20 | 94264432179875 |
| 21 | 472428649241669 |
| 22 | 2366562219717299 |
| 23 | 11850466059333029 |
| 24 | 59322887352366275 |
| 25 | 296896476647946629 |
[1,-1,-1,29,275,1829,10739,59429,318275,1670789, 8656979,44454629,226827875,1151991749,5830280819, 29429454629,148249811075,745630312709, 3745590106259,18797445635429,94264432179875, 472428649241669,2366562219717299, 11850466059333029,59322887352366275, 296896476647946629] |