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| n | a(n) |
|---|---|
| 1 | 21 |
| 2 | 2631 |
| 3 | 311500 |
| 4 | 36959565 |
| 5 | 4383899151 |
| 6 | 519828193272 |
| 7 | 61646570104772 |
| 8 | 7310747898489930 |
| 9 | 866987511530643810 |
| 10 | 102816641533831938240 |
| 11 | 12193094561710087236373 |
| 12 | 1445987266172531006933514 |
[21,2631,311500,36959565,4383899151,519828193272, 61646570104772,7310747898489930, 866987511530643810,102816641533831938240, 12193094561710087236373,1445987266172531006933514] |