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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 9 |
| 3 | 16 |
| 4 | 28 |
| 5 | 56 |
| 6 | 104 |
| 7 | 200 |
| 8 | 380 |
| 9 | 724 |
| 10 | 1380 |
| 11 | 2628 |
| 12 | 5008 |
| 13 | 9540 |
| 14 | 18176 |
| 15 | 34628 |
| 16 | 65972 |
| 17 | 125688 |
| 18 | 239456 |
| 19 | 456204 |
| 20 | 869144 |
| 21 | 1655864 |
| 22 | 3154696 |
| 23 | 6010220 |
| 24 | 11450468 |
| 25 | 21815044 |
| 26 | 41561284 |
| 27 | 79181152 |
| 28 | 150853252 |
| 29 | 287400512 |
| 30 | 547545732 |
| 31 | 1043165604 |
| 32 | 1987403816 |
[2,9,16,28,56,104,200,380,724,1380,2628,5008,9540, 18176,34628,65972,125688,239456,456204,869144, 1655864,3154696,6010220,11450468,21815044, 41561284,79181152,150853252,287400512,547545732, 1043165604,1987403816] |