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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 5 |
| 3 | 25 |
| 4 | 35 |
| 5 | 175 |
| 6 | 385 |
| 7 | 1225 |
| 8 | 1925 |
| 9 | 5005 |
| 10 | 13475 |
| 11 | 25025 |
| 12 | 85085 |
| 13 | 175175 |
| 14 | 425425 |
| 15 | 1616615 |
| 16 | 2977975 |
| 17 | 8083075 |
| 18 | 32757725 |
| 19 | 37182145 |
| 20 | 56581525 |
| 21 | 185910725 |
| 22 | 622396775 |
| 23 | 929553625 |
| 24 | 1301375075 |
| 25 | 4647768125 |
| 26 | 5391411025 |
| 27 | 14315125825 |
| 28 | 26957055125 |
| 29 | 37739877175 |
| 30 | 134785275625 |
[1,5,25,35,175,385,1225,1925,5005,13475,25025, 85085,175175,425425,1616615,2977975,8083075, 32757725,37182145,56581525,185910725,622396775, 929553625,1301375075,4647768125,5391411025, 14315125825,26957055125,37739877175,134785275625] |