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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 4 |
| 3 | 4 |
| 4 | 8 |
| 5 | 12 |
| 6 | 24 |
| 7 | 40 |
| 8 | 80 |
| 9 | 140 |
| 10 | 280 |
| 11 | 504 |
| 12 | 1008 |
| 13 | 1848 |
| 14 | 3696 |
| 15 | 6864 |
| 16 | 13726 |
| 17 | 25740 |
| 18 | 51450 |
| 19 | 97240 |
| 20 | 194210 |
| 21 | 369512 |
| 22 | 737124 |
| 23 | 1410864 |
| 24 | 2810178 |
| 25 | 5408312 |
| 26 | 10752868 |
| 27 | 20801200 |
| 28 | 41273500 |
| 29 | 80233200 |
| 30 | 158851800 |
| 31 | 310235040 |
| 32 | 612835830 |
| 33 | 1202160780 |
| 34 | 2369260560 |
| 35 | 4667212440 |
[2,4,4,8,12,24,40,80,140,280,504,1008,1848,3696, 6864,13726,25740,51450,97240,194210,369512,737124, 1410864,2810178,5408312,10752868,20801200, 41273500,80233200,158851800,310235040,612835830, 1202160780,2369260560,4667212440] |