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| n | a(n) |
|---|---|
| 1 | 4 |
| 2 | 18 |
| 3 | 600 |
| 4 | 35280 |
| 5 | 439084800 |
| 6 | 80951270400 |
| 7 | 6046686277632000 |
| 8 | 2311256907767808000 |
| 9 | 594596384994354462720000 |
| 10 | 256411097818451356681764864000000 |
| 11 | 254907998279515607349492449280000000 |
| 12 | 509258864375374766713691244518493388800000000 |
| 13 | 1371553591139716091434972544191070818271232000000000 |
[4,18,600,35280,439084800,80951270400, 6046686277632000,2311256907767808000, 594596384994354462720000, 256411097818451356681764864000000, 254907998279515607349492449280000000, 509258864375374766713691244518493388800000000, 13715535911397160914349725441910708182712320000000\ 00] |