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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 9 |
| 4 | 83 |
| 5 | 1226 |
| 6 | 24727 |
| 7 | 627909 |
| 8 | 19169758 |
| 9 | 682800001 |
| 10 | 27776711627 |
| 11 | 1270110048234 |
| 12 | 64470498348983 |
| 13 | 3596569233141701 |
| 14 | 218698213338646702 |
| 15 | 14395754017090902609 |
| 16 | 1019782749198898131883 |
| 17 | 77351848007810972904826 |
[1,1,2,9,83,1226,24727,627909,19169758,682800001, 27776711627,1270110048234,64470498348983, 3596569233141701,218698213338646702, 14395754017090902609,1019782749198898131883, 77351848007810972904826] |