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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 16 |
| 4 | 1 |
| 5 | 576 |
| 6 | 496125 |
| 7 | 1 |
| 8 | 41616 |
| 9 | 1830420480 |
| 10 | 375297659043840 |
| 11 | 1 |
| 12 | 5085025 |
| 13 | 10361547386325 |
| 14 | 166557643451782840320 |
| 15 | 5885897714143664700439342125 |
| 16 | 1 |
| 17 | 945193536 |
| 18 | 144188666818560000 |
| 19 | 258848560805325726352932864 |
| 20 | 1192037309255692352595217996892160000 |
| 21 | 36939045170346949681155330481716034613142893328 |
[1,1,16,1,576,496125,1,41616,1830420480, 375297659043840,1,5085025,10361547386325, 166557643451782840320, 5885897714143664700439342125,1,945193536, 144188666818560000,258848560805325726352932864, 1192037309255692352595217996892160000, 36939045170346949681155330481716034613142893328] |