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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 4 |
| 5 | 1 |
| 6 | 61 |
| 7 | 1 |
| 8 | 1681 |
| 9 | 5041 |
| 10 | 15121 |
| 11 | 1 |
| 12 | 13638241 |
| 13 | 1 |
| 14 | 8648641 |
| 15 | 1816214401 |
| 16 | 181880899201 |
| 17 | 1 |
| 18 | 45951781075201 |
| 19 | 1 |
| 20 | 3379365788198401 |
| 21 | 1689515283456001 |
| 22 | 14079294028801 |
| 23 | 1 |
| 24 | 4454857103544668620801 |
| 25 | 538583682060103680001 |
| 26 | 32382376266240001 |
[1,1,1,4,1,61,1,1681,5041,15121,1,13638241,1, 8648641,1816214401,181880899201,1,45951781075201, 1,3379365788198401,1689515283456001, 14079294028801,1,4454857103544668620801, 538583682060103680001,32382376266240001] |