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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 3 |
| 6 | 7 |
| 7 | 23 |
| 8 | 187 |
| 9 | 1049 |
| 10 | 11889 |
| 11 | 241169 |
| 12 | 3461609 |
| 13 | 133910987 |
| 14 | 6440667383 |
| 15 | 259246821927 |
| 16 | 32041224742643 |
| 17 | 3584042412456241 |
| 18 | 447926142061771361 |
| 19 | 160270294066699831201 |
| 20 | 42116645114696072883921 |
| 21 | 17694226961557153345377043 |
| 22 | 16622226330147665886966252007 |
[1,1,1,1,3,7,23,187,1049,11889,241169,3461609, 133910987,6440667383,259246821927,32041224742643, 3584042412456241,447926142061771361, 160270294066699831201,42116645114696072883921, 17694226961557153345377043, 16622226330147665886966252007] |