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| n | a(n) |
|---|---|
| 1 | 15 |
| 2 | 225 |
| 3 | 1695 |
| 4 | 17025 |
| 5 | 159615 |
| 6 | 1535745 |
| 7 | 14661375 |
| 8 | 140355585 |
| 9 | 1342437375 |
| 10 | 12843782145 |
| 11 | 122870296575 |
| 12 | 1175482548225 |
| 13 | 11245539966975 |
| 14 | 107583628673025 |
| 15 | 1029227717656575 |
| 16 | 9846388295204865 |
| 17 | 94198150438322175 |
| 18 | 901172262043910145 |
[15,225,1695,17025,159615,1535745,14661375, 140355585,1342437375,12843782145,122870296575, 1175482548225,11245539966975,107583628673025, 1029227717656575,9846388295204865, 94198150438322175,901172262043910145] |