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| n | a(n) |
|---|---|
| 0 | -1 |
| 1 | 3 |
| 2 | -1 |
| 3 | 7 |
| 4 | 8 |
| 5 | 3 |
| 6 | 12 |
| 7 | 54 |
| 8 | 74 |
| 9 | 133 |
| 10 | 92 |
| 11 | 471 |
| 12 | 296 |
| 13 | 712 |
| 14 | 1152 |
| 15 | 3461 |
| 16 | 4990 |
| 17 | 8684 |
| 18 | 15038 |
| 19 | 14983 |
| 20 | 48719 |
| 21 | 72064 |
| 22 | 76999 |
| 23 | 228269 |
| 24 | 219297 |
| 25 | 429855 |
| 26 | 1013331 |
| 27 | 1003982 |
| 28 | 1942288 |
| 29 | 3142688 |
[-1,3,-1,7,8,3,12,54,74,133,92,471,296,712,1152, 3461,4990,8684,15038,14983,48719,72064,76999, 228269,219297,429855,1013331,1003982,1942288, 3142688] |