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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 55 |
| 4 | 10147 |
| 5 | 21107931 |
| 6 | 511508441781 |
| 7 | 150603715387867113 |
| 8 | 555249505892003620997475 |
| 9 | 26159597034338175244538552103907 |
| 10 | 16021054958659349444630042183181806132953 |
[1,3,55,10147,21107931,511508441781, 150603715387867113,555249505892003620997475, 26159597034338175244538552103907, 16021054958659349444630042183181806132953] |