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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 2 |
| 5 | 4 |
| 6 | 7 |
| 7 | 14 |
| 8 | 32 |
| 9 | 74 |
| 10 | 172 |
| 11 | 408 |
| 12 | 978 |
| 13 | 2349 |
| 14 | 5662 |
| 15 | 13737 |
| 16 | 33568 |
| 17 | 82596 |
| 18 | 204618 |
| 19 | 510208 |
| 20 | 1279544 |
| 21 | 3224828 |
| 22 | 8162144 |
| 23 | 20735397 |
| 24 | 52848816 |
| 25 | 135088609 |
| 26 | 346214873 |
| 27 | 889451320 |
| 28 | 2290164276 |
| 29 | 5908894762 |
| 30 | 15274778235 |
| 31 | 39555942836 |
| 32 | 102603159040 |
| 33 | 266545251022 |
[1,1,1,2,4,7,14,32,74,172,408,978,2349,5662,13737, 33568,82596,204618,510208,1279544,3224828,8162144, 20735397,52848816,135088609,346214873,889451320, 2290164276,5908894762,15274778235,39555942836, 102603159040,266545251022] |