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| n | a(n) |
|---|---|
| 2 | 1 |
| 3 | 5 |
| 4 | 14 |
| 5 | 39 |
| 6 | 108 |
| 7 | 299 |
| 8 | 828 |
| 9 | 2299 |
| 10 | 6401 |
| 11 | 17875 |
| 12 | 50062 |
| 13 | 140601 |
| 14 | 395933 |
| 15 | 1117737 |
| 16 | 3162812 |
| 17 | 8969267 |
| 18 | 25487555 |
| 19 | 72565339 |
| 20 | 206969662 |
| 21 | 591304797 |
| 22 | 1691991626 |
| 23 | 4848703909 |
| 24 | 13914119144 |
| 25 | 39980978277 |
| 26 | 115023510495 |
| 27 | 331303274449 |
[1,5,14,39,108,299,828,2299,6401,17875,50062, 140601,395933,1117737,3162812,8969267,25487555, 72565339,206969662,591304797,1691991626, 4848703909,13914119144,39980978277,115023510495, 331303274449] |