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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 4 |
| 5 | 1 |
| 6 | 9 |
| 7 | 4 |
| 8 | 36 |
| 9 | 36 |
| 10 | 676 |
| 11 | 400 |
| 12 | 9216 |
| 13 | 3600 |
| 14 | 44100 |
| 15 | 36100 |
| 16 | 1223236 |
| 17 | 583696 |
| 18 | 14130081 |
| 19 | 5461569 |
| 20 | 158180929 |
| 21 | 96275344 |
| 22 | 5486661184 |
| 23 | 2454013444 |
| 24 | 179677645456 |
| 25 | 108938283364 |
| 26 | 5446753133584 |
| 27 | 4551557699844 |
| 28 | 280114147765321 |
| 29 | 125264064932449 |
| 30 | 9967796169000201 |
[1,1,1,4,1,9,4,36,36,676,400,9216,3600,44100, 36100,1223236,583696,14130081,5461569,158180929, 96275344,5486661184,2454013444,179677645456, 108938283364,5446753133584,4551557699844, 280114147765321,125264064932449,9967796169000201] |