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| n | a(n) |
|---|---|
| 2 | 120 |
| 3 | 0 |
| 4 | 2400 |
| 5 | 3840 |
| 6 | 63360 |
| 7 | 215040 |
| 8 | 1943040 |
| 9 | 9031680 |
| 10 | 64665600 |
| 11 | 346030080 |
| 12 | 2243911680 |
| 13 | 12792299520 |
| 14 | 79437987840 |
| 15 | 465890181120 |
| 16 | 2838290104320 |
| 17 | 16857940623360 |
| 18 | 101834835886080 |
| 19 | 608260231004160 |
| 20 | 3660556491816960 |
| 21 | 21919358464819200 |
| 22 | 131692072607416320 |
| 23 | 789448748118835200 |
| 24 | 4739507238312345600 |
| 25 | 28425784430470103040 |
[120,0,2400,3840,63360,215040,1943040,9031680, 64665600,346030080,2243911680,12792299520, 79437987840,465890181120,2838290104320, 16857940623360,101834835886080,608260231004160, 3660556491816960,21919358464819200, 131692072607416320,789448748118835200, 4739507238312345600,28425784430470103040] |