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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 9 |
| 4 | 49 |
| 5 | 295 |
| 6 | 1893 |
| 7 | 12697 |
| 8 | 87985 |
| 9 | 625050 |
| 10 | 4527978 |
| 11 | 33321906 |
| 12 | 248416364 |
| 13 | 1872145027 |
| 14 | 14239620722 |
| 15 | 109168322844 |
| 16 | 842720914576 |
| 17 | 6544740855880 |
| 18 | 51099789487093 |
| 19 | 400875949972026 |
| 20 | 3158281869743276 |
| 21 | 24978090277139632 |
| 22 | 198234044661303243 |
| 23 | 1578237110356269055 |
| 24 | 12601524223155447189 |
[1,2,9,49,295,1893,12697,87985,625050,4527978, 33321906,248416364,1872145027,14239620722, 109168322844,842720914576,6544740855880, 51099789487093,400875949972026,3158281869743276, 24978090277139632,198234044661303243, 1578237110356269055,12601524223155447189] |