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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 11 |
| 5 | 34 |
| 6 | 131 |
| 7 | 438 |
| 8 | 2150 |
| 9 | 7676 |
| 10 | 32491 |
| 11 | 116096 |
| 12 | 533186 |
| 13 | 1945184 |
| 14 | 8362152 |
| 15 | 30561808 |
| 16 | 135650378 |
| 17 | 501075616 |
| 18 | 2155759835 |
| 19 | 7986345032 |
| 20 | 34780282521 |
| 21 | 129686419290 |
| 22 | 555913562689 |
| 23 | 2079094345694 |
| 24 | 8947148045345 |
| 25 | 33609869742022 |
[1,1,2,11,34,131,438,2150,7676,32491,116096, 533186,1945184,8362152,30561808,135650378, 501075616,2155759835,7986345032,34780282521, 129686419290,555913562689,2079094345694, 8947148045345,33609869742022] |