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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 9 |
| 2 | 135 |
| 3 | 2835 |
| 4 | 70875 |
| 5 | 1913625 |
| 6 | 63149625 |
| 7 | 2210236875 |
| 8 | 86199238125 |
| 9 | 3878965715625 |
| 10 | 190069320065625 |
| 11 | 9693535323346875 |
| 12 | 533144442784078125 |
| 13 | 30389233238692453125 |
| 14 | 1914521694037624546875 |
| 15 | 124443910112445595546875 |
| 16 | 8586629797758746092734375 |
[1,9,135,2835,70875,1913625,63149625,2210236875, 86199238125,3878965715625,190069320065625, 9693535323346875,533144442784078125, 30389233238692453125,1914521694037624546875, 124443910112445595546875, 8586629797758746092734375] |