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| n | a(n) |
|---|---|
| 1 | 3 |
| 2 | 160 |
| 3 | 417 |
| 4 | 3999 |
| 5 | 19645 |
| 6 | 132039 |
| 7 | 774731 |
| 8 | 4831925 |
| 9 | 29346956 |
| 10 | 180397992 |
| 11 | 1102772445 |
| 12 | 6762537311 |
| 13 | 41387557425 |
| 14 | 253614074287 |
| 15 | 1552946994059 |
| 16 | 9512977716542 |
| 17 | 58262276949109 |
| 18 | 356861142474708 |
| 19 | 2185718698633733 |
[3,160,417,3999,19645,132039,774731,4831925, 29346956,180397992,1102772445,6762537311, 41387557425,253614074287,1552946994059, 9512977716542,58262276949109,356861142474708, 2185718698633733] |