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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 18 |
| 2 | 192 |
| 3 | 1740 |
| 4 | 18140 |
| 5 | 193148 |
| 6 | 2099982 |
| 7 | 23097358 |
| 8 | 255965684 |
| 9 | 2849912436 |
| 10 | 31823439562 |
| 11 | 355996289370 |
| 12 | 3986819767538 |
| 13 | 44679136012334 |
| 14 | 500916612375126 |
| 15 | 5617436087092970 |
| 16 | 63005662878411156 |
| 17 | 706745727675422268 |
[1,18,192,1740,18140,193148,2099982,23097358, 255965684,2849912436,31823439562,355996289370, 3986819767538,44679136012334,500916612375126, 5617436087092970,63005662878411156, 706745727675422268] |