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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 50 |
| 3 | 1000 |
| 4 | 2500 |
| 5 | 20000 |
| 6 | 500000 |
| 7 | 10000000 |
| 8 | 12500000 |
| 9 | 1000000000 |
| 10 | 1000000000 |
| 11 | 90909090910 |
| 12 | 250000000000 |
| 13 | 7692307692308 |
| 14 | 50000000000000 |
| 15 | 200000000000000 |
| 16 | 625000000000000 |
| 17 | 58823529411764706 |
| 18 | 500000000000000000 |
| 19 | 5263157894736842110 |
| 20 | 5000000000000000000 |
[0,50,1000,2500,20000,500000,10000000,12500000, 1000000000,1000000000,90909090910,250000000000, 7692307692308,50000000000000,200000000000000, 625000000000000,58823529411764706, 500000000000000000,5263157894736842110, 5000000000000000000] |