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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 9 |
| 2 | 145 |
| 3 | 2625 |
| 4 | 50049 |
| 5 | 982729 |
| 6 | 19665841 |
| 7 | 398796225 |
| 8 | 8166636545 |
| 9 | 168502295625 |
| 10 | 3497529199185 |
| 11 | 72949645000065 |
| 12 | 1527671538372225 |
| 13 | 32100078290806665 |
| 14 | 676451066002195825 |
| 15 | 14290577765009652865 |
| 16 | 302557549412667613185 |
| 17 | 6417968867896642617225 |
| 18 | 136371773642235542394385 |
[1,9,145,2625,50049,982729,19665841,398796225, 8166636545,168502295625,3497529199185, 72949645000065,1527671538372225,32100078290806665, 676451066002195825,14290577765009652865, 302557549412667613185,6417968867896642617225, 136371773642235542394385] |