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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 3 |
| 4 | 3 |
| 5 | 30 |
| 6 | 135 |
| 7 | 315 |
| 8 | 315 |
| 9 | 11340 |
| 10 | 198450 |
| 11 | 2182950 |
| 12 | 16372125 |
| 13 | 85135050 |
| 14 | 297972675 |
| 15 | 638512875 |
| 16 | 638512875 |
| 17 | 86837751000 |
| 18 | 5861548192500 |
| 19 | 259861969867500 |
| 20 | 8445514020693750 |
| 21 | 212826953321482500 |
| 22 | 4292010225316563750 |
| 23 | 70511596558772118750 |
| 24 | 951906553543423603125 |
| 25 | 10576739483815817812500 |
| 26 | 96248329302723942093750 |
[1,1,3,3,30,135,315,315,11340,198450,2182950, 16372125,85135050,297972675,638512875,638512875, 86837751000,5861548192500,259861969867500, 8445514020693750,212826953321482500, 4292010225316563750,70511596558772118750, 951906553543423603125,10576739483815817812500, 96248329302723942093750] |