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| n | a(n) |
|---|---|
| 1 | 3 |
| 2 | 15 |
| 3 | 15 |
| 4 | 105 |
| 5 | 1155 |
| 6 | 15015 |
| 7 | 255255 |
| 8 | 4849845 |
| 9 | 140645505 |
| 10 | 4360010655 |
| 11 | 178760436855 |
| 12 | 7686698784765 |
| 13 | 453515228301135 |
| 14 | 27664428926369235 |
| 15 | 1964174453772215685 |
| 16 | 143384735125371745005 |
| 17 | 14481858247662546245505 |
[3,15,15,105,1155,15015,255255,4849845,140645505, 4360010655,178760436855,7686698784765, 453515228301135,27664428926369235, 1964174453772215685,143384735125371745005, 14481858247662546245505] |