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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 90 |
| 3 | 392448 |
| 4 | 411264 |
| 5 | 804384 |
| 6 | 871416 |
| 7 | 1284192 |
| 8 | 1935360 |
| 9 | 7456512 |
| 10 | 396168192 |
| 11 | 24193572480 |
| 12 | 43171285248 |
| 13 | 54585498240 |
| 14 | 63178786944 |
| 15 | 123570274464 |
| 16 | 730078562304 |
| 17 | 823442861592 |
| 18 | 1420069242240 |
| 19 | 2354025332736 |
| 20 | 2506251331584 |
| 21 | 3606011136000 |
| 22 | 3697798293504 |
| 23 | 9951618862080 |
[1,90,392448,411264,804384,871416,1284192,1935360, 7456512,396168192,24193572480,43171285248, 54585498240,63178786944,123570274464,730078562304, 823442861592,1420069242240,2354025332736, 2506251331584,3606011136000,3697798293504, 9951618862080] |