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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 9 |
| 3 | 49 |
| 4 | 189 |
| 5 | 945 |
| 6 | 4641 |
| 7 | 21801 |
| 8 | 99021 |
| 9 | 487981 |
| 10 | 2335541 |
| 11 | 10800725 |
| 12 | 51363065 |
| 13 | 238573865 |
| 14 | 1121139065 |
| 15 | 5309312105 |
| 16 | 24543884585 |
| 17 | 113220920945 |
| 18 | 530677144745 |
| 19 | 2439321389945 |
| 20 | 11261499234425 |
| 21 | 52169097691865 |
| 22 | 239433905462945 |
| 23 | 1095710701133345 |
| 24 | 5029918350471545 |
[1,3,9,49,189,945,4641,21801,99021,487981,2335541, 10800725,51363065,238573865,1121139065,5309312105, 24543884585,113220920945,530677144745, 2439321389945,11261499234425,52169097691865, 239433905462945,1095710701133345,5029918350471545] |