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| n | a(n) |
|---|---|
| 1 | 48 |
| 2 | 330 |
| 3 | 1764 |
| 4 | 7968 |
| 5 | 31786 |
| 6 | 117270 |
| 7 | 410460 |
| 8 | 1386380 |
| 9 | 4570334 |
| 10 | 14808240 |
| 11 | 47415150 |
| 12 | 150559236 |
| 13 | 475404140 |
| 14 | 1495840120 |
| 15 | 4696349418 |
| 16 | 14732952836 |
| 17 | 46209158636 |
| 18 | 145045251938 |
| 19 | 455701735566 |
[48,330,1764,7968,31786,117270,410460,1386380, 4570334,14808240,47415150,150559236,475404140, 1495840120,4696349418,14732952836,46209158636, 145045251938,455701735566] |