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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 4 |
| 6 | 1 |
| 7 | 9 |
| 8 | 25 |
| 9 | 49 |
| 10 | 16 |
| 11 | 529 |
| 12 | 841 |
| 13 | 3481 |
| 14 | 16641 |
| 15 | 98596 |
| 16 | 4225 |
| 17 | 2337841 |
| 18 | 13608721 |
| 19 | 67387681 |
| 20 | 264517696 |
| 21 | 6941055969 |
| 22 | 12925188721 |
| 23 | 384768368209 |
| 24 | 5677664356225 |
| 25 | 61935294530404 |
| 26 | 49020596163841 |
| 27 | 16063784753682169 |
[1,1,1,1,4,1,9,25,49,16,529,841,3481,16641,98596, 4225,2337841,13608721,67387681,264517696, 6941055969,12925188721,384768368209,5677664356225, 61935294530404,49020596163841,16063784753682169] |