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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 8 |
| 3 | 248 |
| 4 | 28760 |
| 5 | 12547746 |
| 6 | 20564214798 |
| 7 | 126590463179356 |
| 8 | 2927176521682308228 |
| 9 | 254242270618216007072260 |
| 10 | 82946242184337420844894726534 |
[1,8,248,28760,12547746,20564214798, 126590463179356,2927176521682308228, 254242270618216007072260, 82946242184337420844894726534] |