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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 3 |
| 6 | 5 |
| 7 | 13 |
| 8 | 17 |
| 9 | 45 |
| 10 | 89 |
| 11 | 2453 |
| 12 | 5391 |
| 13 | 90561 |
| 14 | 234023 |
| 15 | 4542721 |
| 16 | 13430469 |
| 17 | 852217819 |
| 18 | 3057070197 |
| 19 | 235450310313 |
| 20 | 994613290405 |
| 21 | 113069663601167 |
| 22 | 560671202395083 |
| 23 | 138912840204968035 |
[1,1,1,1,3,5,13,17,45,89,2453,5391,90561,234023, 4542721,13430469,852217819,3057070197, 235450310313,994613290405,113069663601167, 560671202395083,138912840204968035] |