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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 25 |
| 5 | 16 |
| 6 | 841 |
| 7 | 16641 |
| 8 | 4225 |
| 9 | 13608721 |
| 10 | 264517696 |
| 11 | 12925188721 |
| 12 | 5677664356225 |
| 13 | 49020596163841 |
| 14 | 158432514799144041 |
| 15 | 62586636021357187216 |
| 16 | 1870098771536627436025 |
| 17 | 41998153797159031581158401 |
| 18 | 15402543997324146892198790401 |
[1,1,1,25,16,841,16641,4225,13608721,264517696, 12925188721,5677664356225,49020596163841, 158432514799144041,62586636021357187216, 1870098771536627436025,41998153797159031581158401, 15402543997324146892198790401] |