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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 4 |
| 3 | 18 |
| 4 | 1 |
| 5 | 16 |
| 6 | 324 |
| 7 | 72030 |
| 8 | 162 |
| 9 | 1 |
| 10 | 64 |
| 11 | 5832 |
| 12 | 2916 |
| 13 | 372027810 |
| 14 | 10588410 |
| 15 | 1458 |
| 16 | 1 |
| 17 | 256 |
| 18 | 104976 |
| 19 | 1036385881030500 |
| 20 | 26244 |
| 21 | 9421689827550 |
| 22 | 4946387159463750 |
| 23 | 1556496270 |
| 24 | 13122 |
| 25 | 1 |
| 26 | 1024 |
| 27 | 1889568 |
| 28 | 2542277241000 |
| 29 | 76256028326940 |
| 30 | 236196 |
[1,4,18,1,16,324,72030,162,1,64,5832,2916, 372027810,10588410,1458,1,256,104976, 1036385881030500,26244,9421689827550, 4946387159463750,1556496270,13122,1,1024,1889568, 2542277241000,76256028326940,236196] |