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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 20 |
| 3 | 3200000 |
| 4 | 400 |
| 5 | 512000000000 |
| 6 | 64000000 |
| 7 | 703687441776640000000000000000000000000000000000000000000000 |
| 8 | 8000 |
| 9 | 900719925474099200000000000000000000000000000000000000000000000000000 |
[1,20,3200000,400,512000000000,64000000, 70368744177664000000000000000000000000000000000000\ 0000000000,8000, 90071992547409920000000000000000000000000000000000\ 0000000000000000000] |