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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 4 |
| 4 | 30 |
| 5 | 180 |
| 6 | 462 |
| 7 | 890 |
| 8 | 1532 |
| 9 | 3385 |
| 10 | 19871 |
| 11 | 29040 |
| 12 | 59257 |
| 13 | 66762 |
| 14 | 31545 |
| 15 | 597311 |
| 16 | 1448751 |
| 17 | 1421021 |
| 18 | 1293698 |
| 19 | 12768473 |
| 20 | 2279181 |
| 21 | 147165284 |
| 22 | 118374763 |
| 23 | 821495413 |
| 24 | 2618883054 |
| 25 | 2247521689 |
| 26 | 3145845927 |
| 27 | 7650216016 |
| 28 | 27357920380 |
| 29 | 22859974504 |
| 30 | 189924891289 |
| 31 | 78076882908 |
| 32 | 189573830057 |
[1,2,4,30,180,462,890,1532,3385,19871,29040,59257, 66762,31545,597311,1448751,1421021,1293698, 12768473,2279181,147165284,118374763,821495413, 2618883054,2247521689,3145845927,7650216016, 27357920380,22859974504,189924891289,78076882908, 189573830057] |