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| n | a(n) |
|---|---|
| 1 | 56 |
| 2 | 1231 |
| 3 | 158473 |
| 4 | 15255786 |
| 5 | 1107664956 |
| 6 | 68107762118 |
| 7 | 3886911446418 |
[56,1231,158473,15255786,1107664956,68107762118, 3886911446418] |