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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 5 |
| 3 | 12 |
| 4 | 28 |
| 5 | 66 |
| 6 | 156 |
| 7 | 368 |
| 8 | 868 |
| 9 | 2048 |
| 10 | 4832 |
| 11 | 11400 |
| 12 | 26896 |
| 13 | 63456 |
| 14 | 149712 |
| 15 | 353216 |
| 16 | 833344 |
| 17 | 1966112 |
| 18 | 4638656 |
| 19 | 10944000 |
| 20 | 25820224 |
| 21 | 60917760 |
| 22 | 143723520 |
| 23 | 339087488 |
| 24 | 800010496 |
| 25 | 1887468032 |
| 26 | 4453111040 |
| 27 | 10506243072 |
| 28 | 24787422208 |
| 29 | 58481066496 |
[2,5,12,28,66,156,368,868,2048,4832,11400,26896, 63456,149712,353216,833344,1966112,4638656, 10944000,25820224,60917760,143723520,339087488, 800010496,1887468032,4453111040,10506243072, 24787422208,58481066496] |