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| n | a(n) |
|---|---|
| 1 | 18 |
| 2 | 135 |
| 3 | 891 |
| 4 | 4095 |
| 5 | 10560 |
| 6 | 13120 |
| 7 | 14144 |
| 8 | 21600 |
| 9 | 23199 |
| 10 | 74655 |
| 11 | 144495 |
| 12 | 192311 |
| 13 | 404415 |
| 14 | 4197375 |
| 15 | 4612608 |
| 16 | 5675775 |
| 17 | 6664680 |
| 18 | 9180800 |
| 19 | 10953215 |
| 20 | 11110400 |
| 21 | 14381055 |
| 22 | 18162144 |
| 23 | 18420480 |
| 24 | 18920000 |
| 25 | 20765024 |
| 26 | 25159680 |
| 27 | 32058351 |
| 28 | 41055200 |
| 29 | 55889920 |
| 30 | 65327104 |
| 31 | 65982464 |
[18,135,891,4095,10560,13120,14144,21600,23199, 74655,144495,192311,404415,4197375,4612608, 5675775,6664680,9180800,10953215,11110400, 14381055,18162144,18420480,18920000,20765024, 25159680,32058351,41055200,55889920,65327104, 65982464] |