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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 6 |
| 4 | 32 |
| 5 | 390 |
| 6 | 16444 |
| 7 | 4013544 |
| 8 | 11784471548 |
| 9 | 1168225267521350 |
| 10 | 16816734263788624008200 |
| 11 | 276565526698898057002583240473088 |
| 12 | 96052644365764024805972019009272150642974291708 |
| 13 | 43586702014259316987395017345466711329303914541873541942193666197800 |
[1,1,2,6,32,390,16444,4013544,11784471548, 1168225267521350,16816734263788624008200, 276565526698898057002583240473088, 96052644365764024805972019009272150642974291708, 43586702014259316987395017345466711329303914541873\ 541942193666197800] |