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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 4 |
| 3 | 10 |
| 4 | 22 |
| 5 | 46 |
| 6 | 96 |
| 7 | 198 |
| 8 | 406 |
| 9 | 826 |
| 10 | 1668 |
| 11 | 3362 |
| 12 | 6770 |
| 13 | 13590 |
| 14 | 27248 |
| 15 | 54614 |
| 16 | 109378 |
| 17 | 218946 |
| 18 | 438180 |
| 19 | 876738 |
| 20 | 1753998 |
| 21 | 3508726 |
| 22 | 7018368 |
| 23 | 14038006 |
| 24 | 28077846 |
| 25 | 56157954 |
| 26 | 112318900 |
| 27 | 224642090 |
| 28 | 449289666 |
| 29 | 898586438 |
| 30 | 1797182704 |
| 31 | 3594378014 |
| 32 | 7188772666 |
| 33 | 14377567834 |
| 34 | 28755164100 |
| 35 | 57510365698 |
| 36 | 115020782350 |
| 37 | 230041628622 |
| 38 | 460083340304 |
| 39 | 920166792942 |
[1,2,4,10,22,46,96,198,406,826,1668,3362,6770, 13590,27248,54614,109378,218946,438180,876738, 1753998,3508726,7018368,14038006,28077846, 56157954,112318900,224642090,449289666,898586438, 1797182704,3594378014,7188772666,14377567834, 28755164100,57510365698,115020782350,230041628622, 460083340304,920166792942] |