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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 5 |
| 2 | 45 |
| 3 | 610 |
| 4 | 11020 |
| 5 | 248870 |
| 6 | 6744350 |
| 7 | 213233400 |
| 8 | 7704814200 |
| 9 | 313199930400 |
| 10 | 14146162064400 |
| 11 | 702826758144000 |
| 12 | 38093116667766000 |
| 13 | 2236695336601458000 |
| 14 | 141433354184701746000 |
| 15 | 9582086196220281456000 |
| 16 | 692463727252196674560000 |
[1,5,45,610,11020,248870,6744350,213233400, 7704814200,313199930400,14146162064400, 702826758144000,38093116667766000, 2236695336601458000,141433354184701746000, 9582086196220281456000,692463727252196674560000] |