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| n | a(n) |
|---|---|
| 9 | 1 |
| 10 | 30 |
| 11 | 528 |
| 12 | 7140 |
| 13 | 82251 |
| 14 | 850668 |
| 15 | 8145060 |
| 16 | 73629072 |
| 17 | 636763050 |
| 18 | 5317936260 |
| 19 | 43183019880 |
| 20 | 342700125300 |
| 21 | 2668424446233 |
| 22 | 20448884000160 |
| 23 | 154603005527328 |
| 24 | 1155454041309504 |
| 25 | 8550047575185300 |
| 26 | 62724534168736440 |
[1,30,528,7140,82251,850668,8145060,73629072, 636763050,5317936260,43183019880,342700125300, 2668424446233,20448884000160,154603005527328, 1155454041309504,8550047575185300, 62724534168736440] |