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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 10 |
| 2 | 18 |
| 3 | 134 |
| 4 | 626 |
| 5 | 4254 |
| 6 | 25850 |
| 7 | 177270 |
| 8 | 1192450 |
| 9 | 8392846 |
| 10 | 59270218 |
| 11 | 427294630 |
| 12 | 3103586514 |
| 13 | 22805459262 |
| 14 | 168767740698 |
| 15 | 1258575706582 |
| 16 | 9441189199010 |
| 17 | 71224314198510 |
| 18 | 539889535264490 |
| 19 | 4110514381564422 |
| 20 | 31418080601125746 |
[1,10,18,134,626,4254,25850,177270,1192450, 8392846,59270218,427294630,3103586514,22805459262, 168767740698,1258575706582,9441189199010, 71224314198510,539889535264490,4110514381564422, 31418080601125746] |