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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 120 |
| 2 | 13608000 |
| 3 | 2288430144000000 |
| 4 | 699207483978843840000000000 |
| 5 | 435858496811697532778806061260800000000000 |
| 6 | 597507154003470929939550139366865942134606725120000000000000 |
| 7 | 1898554530971015145216561379837863419725314413457243266261094236160000000000000000 |
[1,120,13608000,2288430144000000, 699207483978843840000000000, 435858496811697532778806061260800000000000, 59750715400347092993955013936686594213460672512000\ 0000000000, 18985545309710151452165613798378634197253144134572\ 43266261094236160000000000000000] |