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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 27 |
| 4 | 324 |
| 5 | 4455 |
| 6 | 66339 |
| 7 | 1041012 |
| 8 | 16953624 |
| 9 | 283848543 |
| 10 | 4855304025 |
| 11 | 84482290035 |
| 12 | 1490628232080 |
| 13 | 26607713942628 |
| 14 | 479621100042756 |
| 15 | 8718235759397880 |
| 16 | 159628084420459248 |
| 17 | 2941328850997439439 |
| 18 | 54501093415540789605 |
| 19 | 1014898739548854163185 |
[1,3,27,324,4455,66339,1041012,16953624,283848543, 4855304025,84482290035,1490628232080, 26607713942628,479621100042756,8718235759397880, 159628084420459248,2941328850997439439, 54501093415540789605,1014898739548854163185] |