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| n | a(n) |
|---|---|
| 1 | 5 |
| 2 | 15 |
| 3 | 16 |
| 4 | 25 |
| 5 | 75 |
| 6 | 235 |
| 7 | 475 |
| 8 | 515 |
| 9 | 516 |
| 10 | 725 |
| 11 | 5125 |
| 12 | 7525 |
| 13 | 22925 |
| 14 | 23585 |
| 15 | 72475 |
| 16 | 505525 |
| 17 | 515415 |
| 18 | 2501125 |
| 19 | 15008516 |
| 20 | 23711235 |
| 21 | 72267325 |
| 22 | 149081275 |
| 23 | 250133275 |
| 24 | 256032335 |
| 25 | 505228925 |
| 26 | 2294919525 |
| 27 | 5153315075 |
| 28 | 15040686675 |
| 29 | 50222133125 |
[5,15,16,25,75,235,475,515,516,725,5125,7525, 22925,23585,72475,505525,515415,2501125,15008516, 23711235,72267325,149081275,250133275,256032335, 505228925,2294919525,5153315075,15040686675, 50222133125] |