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| n | a(n) |
|---|---|
| 2 | 4 |
| 3 | 15 |
| 4 | 12 |
| 5 | 25 |
| 6 | 55 |
| 7 | 112 |
| 8 | 188 |
| 9 | 438 |
| 10 | 789 |
| 11 | 1573 |
| 12 | 3135 |
| 13 | 5980 |
| 14 | 11848 |
| 15 | 23035 |
| 16 | 45020 |
| 17 | 87873 |
| 18 | 171910 |
| 19 | 335464 |
| 20 | 655397 |
| 21 | 1281190 |
| 22 | 2501173 |
| 23 | 4888098 |
| 24 | 9548543 |
| 25 | 18653025 |
| 26 | 36441500 |
| 27 | 71190933 |
| 28 | 139076320 |
| 29 | 271694910 |
| 30 | 530784135 |
| 31 | 1036914040 |
| 32 | 2025703900 |
| 33 | 3957367099 |
| 34 | 7731003525 |
[4,15,12,25,55,112,188,438,789,1573,3135,5980, 11848,23035,45020,87873,171910,335464,655397, 1281190,2501173,4888098,9548543,18653025,36441500, 71190933,139076320,271694910,530784135,1036914040, 2025703900,3957367099,7731003525] |