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| n | a(n) |
|---|---|
| 2 | 2 |
| 3 | 3 |
| 4 | 5 |
| 5 | 23 |
| 6 | 239 |
| 7 | 719 |
| 8 | 5039 |
| 9 | 201599 |
| 10 | 1088639 |
| 11 | 14515199 |
| 12 | 159667199 |
| 13 | 479001599 |
| 14 | 31135103999 |
| 15 | 87178291199 |
| 16 | 2615348735999 |
| 17 | 188305108991999 |
| 18 | 711374856191999 |
| 19 | 192071211171839999 |
| 20 | 3649353012264959999 |
| 21 | 12164510040883199999 |
| 22 | 2248001455555215359999 |
| 23 | 2248001455555215359999 |
[2,3,5,23,239,719,5039,201599,1088639,14515199, 159667199,479001599,31135103999,87178291199, 2615348735999,188305108991999,711374856191999, 192071211171839999,3649353012264959999, 12164510040883199999,2248001455555215359999, 2248001455555215359999] |