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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 9 |
| 3 | 68 |
| 4 | 549 |
| 5 | 4819 |
| 6 | 43506 |
| 7 | 397756 |
| 8 | 3681943 |
| 9 | 34344296 |
| 10 | 322199867 |
| 11 | 3036544958 |
| 12 | 28722439343 |
| 13 | 272501681533 |
| 14 | 2591959274190 |
[1,9,68,549,4819,43506,397756,3681943,34344296, 322199867,3036544958,28722439343,272501681533, 2591959274190] |