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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 3 |
| 3 | 23 |
| 4 | 47 |
| 5 | 231 |
| 6 | 2260 |
| 7 | 6527 |
| 8 | 35151 |
| 9 | 224759 |
| 10 | 3434124 |
| 11 | 12476055 |
| 12 | 79758206 |
| 13 | 491191521 |
| 14 | 4752819625 |
| 15 | 105146082344 |
| 16 | 393097093065 |
| 17 | 2976053272527 |
| 18 | 21569670506914 |
| 19 | 188844207315245 |
| 20 | 2277243901499454 |
| 21 | 72603521472295945 |
| 22 | 326137558352646889 |
| 23 | 2491611720654851668 |
[1,2,3,23,47,231,2260,6527,35151,224759,3434124, 12476055,79758206,491191521,4752819625, 105146082344,393097093065,2976053272527, 21569670506914,188844207315245,2277243901499454, 72603521472295945,326137558352646889, 2491611720654851668] |