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| n | a(n) |
|---|---|
| 1 | 3 |
| 2 | 27 |
| 3 | 243 |
| 4 | 2028 |
| 5 | 16428 |
| 6 | 129792 |
| 7 | 1009200 |
| 8 | 7756992 |
| 9 | 59140800 |
| 10 | 448278528 |
| 11 | 3383655168 |
| 12 | 25462705152 |
| 13 | 191189978112 |
| 14 | 1433272320000 |
| 15 | 10732091092992 |
| 16 | 80291457712128 |
| 17 | 600321157939200 |
| 18 | 4486422252748800 |
| 19 | 33517530883227648 |
[3,27,243,2028,16428,129792,1009200,7756992, 59140800,448278528,3383655168,25462705152, 191189978112,1433272320000,10732091092992, 80291457712128,600321157939200,4486422252748800, 33517530883227648] |