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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 9 |
| 4 | 258 |
| 5 | 293685 |
| 6 | 531124770570 |
| 7 | 2439717292075827330588969 |
| 8 | 72554628124279239546273779187960042205300343234178 |
[1,2,9,258,293685,531124770570, 2439717292075827330588969, 72554628124279239546273779187960042205300343234178\ ] |