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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 10 |
| 3 | 144 |
| 4 | 2240 |
| 5 | 36402 |
| 6 | 605600 |
| 7 | 10231704 |
| 8 | 174721408 |
| 9 | 3007128087 |
| 10 | 52066422332 |
| 11 | 905751324518 |
| 12 | 15816420350420 |
| 13 | 277052021262480 |
| 14 | 4865694946445860 |
| 15 | 85641691341319812 |
| 16 | 1510236415306298800 |
| 17 | 26675550244540566147 |
[1,10,144,2240,36402,605600,10231704,174721408, 3007128087,52066422332,905751324518, 15816420350420,277052021262480,4865694946445860, 85641691341319812,1510236415306298800, 26675550244540566147] |