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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 9 |
| 3 | 4 |
| 4 | 60 |
| 5 | 81 |
| 6 | 6 |
| 7 | 570 |
| 8 | 3600 |
| 9 | 576 |
| 10 | 9 |
| 11 | 6960 |
| 12 | 324900 |
| 13 | 178068 |
| 14 | 3969 |
| 15 | 12 |
| 16 | 104006 |
| 17 | 48441600 |
| 18 | 157322070 |
| 19 | 8459154 |
| 20 | 25281 |
| 21 | 16 |
| 22 | 1837752 |
| 23 | 10817248036 |
| 24 | 292870561470 |
| 25 | 73055876226 |
| 26 | 376812420 |
| 27 | 155236 |
| 28 | 20 |
| 29 | 37478718 |
| 30 | 3377332413504 |
| 31 | 994136348047368 |
[2,9,4,60,81,6,570,3600,576,9,6960,324900,178068, 3969,12,104006,48441600,157322070,8459154,25281, 16,1837752,10817248036,292870561470,73055876226, 376812420,155236,20,37478718,3377332413504, 994136348047368] |