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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 15 |
| 3 | 198 |
| 4 | 2578 |
| 5 | 33519 |
| 6 | 435753 |
| 7 | 5664796 |
| 8 | 73642356 |
| 9 | 957350637 |
| 10 | 12445558291 |
| 11 | 161792257794 |
| 12 | 2103299351334 |
| 13 | 355457590375459 |
| 14 | 60072332773452585 |
| 15 | 10152224238713486880 |
| 16 | 1715725896342579282736 |
| 17 | 289957676481895898782401 |
[1,15,198,2578,33519,435753,5664796,73642356, 957350637,12445558291,161792257794,2103299351334, 355457590375459,60072332773452585, 10152224238713486880,1715725896342579282736, 289957676481895898782401] |