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| n | a(n) |
|---|---|
| 0 | 2 |
| 1 | 9 |
| 2 | 54 |
| 3 | 441 |
| 4 | 4410 |
| 5 | 53361 |
| 6 | 747054 |
| 7 | 12006225 |
| 8 | 216112050 |
| 9 | 4334247225 |
| 10 | 95353438950 |
| 11 | 2292816782025 |
| 12 | 59613236332650 |
| 13 | 1671463434096225 |
| 14 | 50143903022886750 |
| 15 | 1606276360166472225 |
| 16 | 54613396245660055650 |
| 17 | 1967688541203928475625 |
| 18 | 74772164565749282073750 |
[2,9,54,441,4410,53361,747054,12006225,216112050, 4334247225,95353438950,2292816782025, 59613236332650,1671463434096225,50143903022886750, 1606276360166472225,54613396245660055650, 1967688541203928475625,74772164565749282073750] |