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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 7 |
| 4 | 17 |
| 5 | 47 |
| 6 | 102 |
| 7 | 255 |
| 8 | 556 |
| 9 | 1272 |
| 10 | 2766 |
| 11 | 6143 |
| 12 | 13183 |
| 13 | 28671 |
| 14 | 61182 |
| 15 | 131017 |
| 16 | 277952 |
| 17 | 589823 |
| 18 | 1243800 |
| 19 | 2621439 |
| 20 | 5502191 |
| 21 | 11534073 |
| 22 | 24111102 |
| 23 | 50331647 |
| 24 | 104843732 |
| 25 | 218103760 |
| 26 | 452956158 |
| 27 | 939522816 |
| 28 | 1946095599 |
| 29 | 4026531839 |
| 30 | 8321365194 |
[1,2,7,17,47,102,255,556,1272,2766,6143,13183, 28671,61182,131017,277952,589823,1243800,2621439, 5502191,11534073,24111102,50331647,104843732, 218103760,452956158,939522816,1946095599, 4026531839,8321365194] |