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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 9 |
| 2 | 117 |
| 3 | 1542 |
| 4 | 19404 |
| 5 | 239481 |
| 6 | 2900802 |
| 7 | 34609797 |
| 8 | 407615175 |
| 9 | 4747112731 |
| 10 | 54743025339 |
| 11 | 625791326688 |
| 12 | 7097863351275 |
| 13 | 79938092898747 |
| 14 | 894514969436076 |
| 15 | 9951032414168964 |
| 16 | 110103625982603466 |
| 17 | 1212181195307220126 |
| 18 | 13283829023674846878 |
| 19 | 144946503880942833774 |
[1,9,117,1542,19404,239481,2900802,34609797, 407615175,4747112731,54743025339,625791326688, 7097863351275,79938092898747,894514969436076, 9951032414168964,110103625982603466, 1212181195307220126,13283829023674846878, 144946503880942833774] |