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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 2 |
| 3 | 5 |
| 4 | 22 |
| 5 | 115 |
| 6 | 698 |
| 7 | 4925 |
| 8 | 39622 |
| 9 | 357955 |
| 10 | 3589178 |
| 11 | 39558845 |
| 12 | 475412422 |
| 13 | 6187461955 |
| 14 | 86702878778 |
| 15 | 1301486906045 |
| 16 | 20836087009222 |
| 17 | 354385941189955 |
| 18 | 6381537618718778 |
| 19 | 121290714467642045 |
| 20 | 2426520470557921222 |
| 21 | 50969651457241797955 |
| 22 | 1121574207307049758778 |
[0,1,2,5,22,115,698,4925,39622,357955,3589178, 39558845,475412422,6187461955,86702878778, 1301486906045,20836087009222,354385941189955, 6381537618718778,121290714467642045, 2426520470557921222,50969651457241797955, 1121574207307049758778] |