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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 15 |
| 4 | 113 |
| 5 | 1153 |
| 6 | 15125 |
| 7 | 245829 |
| 8 | 4815403 |
| 9 | 111308699 |
| 10 | 2985997351 |
| 11 | 91712874487 |
| 12 | 3189130896077 |
| 13 | 124366296990757 |
| 14 | 5395176819674205 |
| 15 | 258547307299130037 |
| 16 | 13603419571939001827 |
| 17 | 781604484498111072195 |
| 18 | 48806254671145521802863 |
| 19 | 3298007680091577596528415 |
[1,1,3,15,113,1153,15125,245829,4815403,111308699, 2985997351,91712874487,3189130896077, 124366296990757,5395176819674205, 258547307299130037,13603419571939001827, 781604484498111072195,48806254671145521802863, 3298007680091577596528415] |