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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 3 |
| 2 | 33 |
| 3 | 312 |
| 4 | 2868 |
| 5 | 26133 |
| 6 | 237147 |
| 7 | 2146992 |
| 8 | 19409064 |
| 9 | 175287597 |
| 10 | 1581968247 |
| 11 | 14270061192 |
| 12 | 128673729492 |
| 13 | 1159919095227 |
| 14 | 10453609519917 |
| 15 | 94194476541312 |
| 16 | 848633286566256 |
| 17 | 7644719039897661 |
| 18 | 68858679361873263 |
| 19 | 620181110747360616 |
| 20 | 5585301978207342396 |
| 21 | 50297638075074093723 |
| 22 | 452923691790915847653 |
[0,3,33,312,2868,26133,237147,2146992,19409064, 175287597,1581968247,14270061192,128673729492, 1159919095227,10453609519917,94194476541312, 848633286566256,7644719039897661, 68858679361873263,620181110747360616, 5585301978207342396,50297638075074093723, 452923691790915847653] |