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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 13 |
| 2 | 7778742049 |
| 3 | 215414832505658809004682396169711233230800418578767753330908886771798637 |
[1,13,7778742049, 21541483250565880900468239616971123323080041857876\ 7753330908886771798637] |