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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 1 |
| 6 | 1 |
| 7 | 11 |
| 8 | 17 |
| 9 | 249 |
| 10 | 505 |
| 11 | 5595 |
| 12 | 13277 |
| 13 | 255723 |
| 14 | 714985 |
| 15 | 48904687 |
| 16 | 172919585 |
| 17 | 23239333565 |
| 18 | 103253283519 |
| 19 | 18873899120725 |
| 20 | 102743668838719 |
| 21 | 32633484992496285 |
| 22 | 217183989203759529 |
| 23 | 151537474245121050379 |
[1,1,1,1,1,1,11,17,249,505,5595,13277,255723, 714985,48904687,172919585,23239333565, 103253283519,18873899120725,102743668838719, 32633484992496285,217183989203759529, 151537474245121050379] |