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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 8 |
| 3 | 101 |
| 4 | 1569 |
| 5 | 27445 |
| 6 | 518407 |
| 7 | 10333243 |
| 8 | 214320244 |
| 9 | 4583132411 |
| 10 | 100411556533 |
| 11 | 2243625355010 |
| 12 | 50955869372055 |
| 13 | 1173262656151429 |
| 14 | 27332509319090516 |
| 15 | 643208905017756216 |
| 16 | 15270427859720369204 |
| 17 | 365356267775348553277 |
| 18 | 8801688936499808334602 |
[1,1,8,101,1569,27445,518407,10333243,214320244, 4583132411,100411556533,2243625355010, 50955869372055,1173262656151429,27332509319090516, 643208905017756216,15270427859720369204, 365356267775348553277,8801688936499808334602] |