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| n | a(n) |
|---|---|
| 1 | 7 |
| 2 | 39 |
| 3 | 281 |
| 4 | 1774 |
| 5 | 11385 |
| 6 | 73136 |
| 7 | 472638 |
| 8 | 3050285 |
| 9 | 19667721 |
| 10 | 126807809 |
| 11 | 817795362 |
| 12 | 5274346426 |
| 13 | 34015377046 |
| 14 | 219367395594 |
| 15 | 1414720693245 |
| 16 | 9123720789554 |
| 17 | 58840106012423 |
| 18 | 379467286876826 |
| 19 | 2447231592206585 |
| 20 | 15782503349398343 |
[7,39,281,1774,11385,73136,472638,3050285, 19667721,126807809,817795362,5274346426, 34015377046,219367395594,1414720693245, 9123720789554,58840106012423,379467286876826, 2447231592206585,15782503349398343] |