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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 8 |
| 3 | 48 |
| 4 | 188 |
| 5 | 1196 |
| 6 | 3044 |
| 7 | 23636 |
| 8 | 75116 |
| 9 | 366836 |
| 10 | 1105860 |
| 11 | 8160180 |
| 12 | 18976804 |
| 13 | 143784004 |
| 14 | 384483604 |
| 15 | 1625423764 |
| 16 | 6434066884 |
| 17 | 43771766404 |
| 18 | 98222578204 |
| 19 | 734437326604 |
| 20 | 1837209557164 |
| 21 | 8296304050444 |
| 22 | 29337293687644 |
| 23 | 210472769694844 |
| 24 | 468453599159644 |
| 25 | 2996665727914684 |
[2,8,48,188,1196,3044,23636,75116,366836,1105860, 8160180,18976804,143784004,384483604,1625423764, 6434066884,43771766404,98222578204,734437326604, 1837209557164,8296304050444,29337293687644, 210472769694844,468453599159644,2996665727914684] |