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| n | a(n) |
|---|---|
| 3 | 24 |
| 4 | 54 |
| 5 | 216 |
| 6 | 648 |
| 7 | 2376 |
| 8 | 8100 |
| 9 | 29232 |
| 10 | 104544 |
| 11 | 381672 |
| 12 | 1397070 |
| 13 | 5163480 |
| 14 | 19170432 |
| 15 | 71587080 |
| 16 | 268423200 |
| 17 | 1010595960 |
| 18 | 3817704744 |
| 19 | 14467313448 |
| 20 | 54975424194 |
| 21 | 209430985176 |
| 22 | 799644248064 |
| 23 | 3059511345864 |
| 24 | 11728121930100 |
| 25 | 45035998958016 |
| 26 | 173215362539520 |
| 27 | 667199954727936 |
[24,54,216,648,2376,8100,29232,104544,381672, 1397070,5163480,19170432,71587080,268423200, 1010595960,3817704744,14467313448,54975424194, 209430985176,799644248064,3059511345864, 11728121930100,45035998958016,173215362539520, 667199954727936] |