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| n | a(n) |
|---|---|
| 1 | 126 |
| 2 | 250 |
| 3 | 496 |
| 4 | 984 |
| 5 | 1952 |
| 6 | 3872 |
| 7 | 7680 |
| 8 | 15234 |
| 9 | 30218 |
| 10 | 59940 |
| 11 | 118896 |
| 12 | 235840 |
| 13 | 467808 |
| 14 | 927936 |
| 15 | 1840638 |
| 16 | 3651058 |
| 17 | 7242176 |
| 18 | 14365456 |
| 19 | 28495072 |
| 20 | 56522336 |
| 21 | 112116736 |
| 22 | 222392834 |
| 23 | 441134610 |
| 24 | 875027044 |
| 25 | 1735688632 |
| 26 | 3442882192 |
| 27 | 6829242048 |
[126,250,496,984,1952,3872,7680,15234,30218,59940, 118896,235840,467808,927936,1840638,3651058, 7242176,14365456,28495072,56522336,112116736, 222392834,441134610,875027044,1735688632, 3442882192,6829242048] |