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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 13 |
| 3 | 6500 |
| 4 | 262769000 |
| 5 | 1500305882400000 |
| 6 | 1885591784499143760000000 |
| 7 | 753074404854223679800035840000000000 |
| 8 | 130639388303516205847055577677763494400000000000000 |
[1,13,6500,262769000,1500305882400000, 1885591784499143760000000, 753074404854223679800035840000000000, 13063938830351620584705557767776349440000000000000\ 0] |