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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 8 |
| 4 | 35 |
| 5 | 181 |
| 6 | 1042 |
| 7 | 6301 |
| 8 | 39435 |
| 9 | 249744 |
| 10 | 1585386 |
| 11 | 10027385 |
| 12 | 62696192 |
| 13 | 385398251 |
| 14 | 2322152120 |
| 15 | 13727653882 |
| 16 | 80274175978 |
| 17 | 472701550856 |
| 18 | 2883417403654 |
| 19 | 18796497074750 |
| 20 | 132728456810968 |
| 21 | 995480740265410 |
| 22 | 7605881152587204 |
| 23 | 56821415293287735 |
| 24 | 403362682583930224 |
[1,1,2,8,35,181,1042,6301,39435,249744,1585386, 10027385,62696192,385398251,2322152120, 13727653882,80274175978,472701550856, 2883417403654,18796497074750,132728456810968, 995480740265410,7605881152587204, 56821415293287735,403362682583930224] |