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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 6 |
| 4 | 42 |
| 5 | 630 |
| 6 | 57330 |
| 7 | 219172590 |
| 8 | 2287458514758690 |
| 9 | 523246645674205487113407810300 |
| 10 | 34223381526163442974989472671319545640510650941743506071550 |
| 11 | 65068880171408068403202506207461768112305307530373013598603234255112994800902512713302330140957468591804616490482800 |
[1,2,6,42,630,57330,219172590,2287458514758690, 523246645674205487113407810300, 34223381526163442974989472671319545640510650941743\ 506071550, 65068880171408068403202506207461768112305307530373\ 01359860323425511299480090251271330233014095746859\ 1804616490482800] |