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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 5 |
| 5 | 15 |
| 6 | 49 |
| 7 | 168 |
| 8 | 596 |
| 9 | 2170 |
| 10 | 8063 |
| 11 | 30451 |
| 12 | 116545 |
| 13 | 451038 |
| 14 | 1762065 |
| 15 | 6939684 |
| 16 | 27523374 |
| 17 | 109832228 |
| 18 | 440668881 |
| 19 | 1776599145 |
| 20 | 7193526536 |
| 21 | 29240389629 |
| 22 | 119276102017 |
| 23 | 488106369196 |
| 24 | 2003299984825 |
| 25 | 8244088853598 |
| 26 | 34010402405020 |
| 27 | 140627814353509 |
| 28 | 582704045483909 |
| 29 | 2419228983607503 |
| 30 | 10062353339406026 |
| 31 | 41924039720446064 |
| 32 | 174952464642171681 |
| 33 | 731184941189099208 |
| 34 | 3060168941260579386 |
[1,1,2,5,15,49,168,596,2170,8063,30451,116545, 451038,1762065,6939684,27523374,109832228, 440668881,1776599145,7193526536,29240389629, 119276102017,488106369196,2003299984825, 8244088853598,34010402405020,140627814353509, 582704045483909,2419228983607503, 10062353339406026,41924039720446064, 174952464642171681,731184941189099208, 3060168941260579386] |