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| n | a(n) |
|---|---|
| 1 | 3 |
| 2 | 21 |
| 3 | 903 |
| 4 | 1631721 |
| 5 | 5325028475403 |
| 6 | 56711856527710922180500221 |
| 7 | 82753323662259982099234097722219590008756576353188748920925694383267934319786203404455994065868822592721 |
[3,21,903,1631721,5325028475403, 56711856527710922180500221, 82753323662259982099234097722219590008756576353188\ 74892092569438326793431978620340445599406586882259\ 2721] |