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| n | a(n) |
|---|---|
| 5 | 31 |
| 6 | 1305 |
| 7 | 4955 |
| 8 | 26765 |
| 9 | 124450 |
| 10 | 2008546 |
| 11 | 4399870 |
| 12 | 17016950 |
| 13 | 51516925 |
| 14 | 187653115 |
| 15 | 2298210803 |
| 16 | 4405690315 |
| 17 | 14002637160 |
| 18 | 37448507530 |
| 19 | 109070884580 |
| 20 | 308549728478 |
| 21 | 3711879979775 |
| 22 | 6377942356265 |
| 23 | 19056675979455 |
| 24 | 45667548869495 |
| 25 | 122550455798230 |
| 26 | 293681447602030 |
[31,1305,4955,26765,124450,2008546,4399870, 17016950,51516925,187653115,2298210803,4405690315, 14002637160,37448507530,109070884580,308549728478, 3711879979775,6377942356265,19056675979455, 45667548869495,122550455798230,293681447602030] |