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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 6 |
| 3 | 12 |
| 4 | 20 |
| 5 | 40 |
| 6 | 88 |
| 7 | 176 |
| 8 | 272 |
| 9 | 544 |
| 10 | 1760 |
| 11 | 3520 |
| 12 | 4416 |
| 13 | 8832 |
| 14 | 28032 |
| 15 | 56064 |
| 16 | 65792 |
| 17 | 131584 |
| 18 | 396800 |
| 19 | 793600 |
| 20 | 1332224 |
| 21 | 2664448 |
| 22 | 5986304 |
| 23 | 11972608 |
| 24 | 16846848 |
| 25 | 33693696 |
| 26 | 101638144 |
| 27 | 203276288 |
| 28 | 340869120 |
| 29 | 681738240 |
| 30 | 1533902848 |
| 31 | 3067805696 |
| 32 | 4295032832 |
| 33 | 8590065664 |
[1,2,6,12,20,40,88,176,272,544,1760,3520,4416, 8832,28032,56064,65792,131584,396800,793600, 1332224,2664448,5986304,11972608,16846848, 33693696,101638144,203276288,340869120,681738240, 1533902848,3067805696,4295032832,8590065664] |