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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 4 |
| 4 | 9 |
| 5 | 20 |
| 6 | 43 |
| 7 | 89 |
| 8 | 181 |
| 9 | 365 |
| 10 | 734 |
| 11 | 1473 |
| 12 | 2952 |
| 13 | 5911 |
| 14 | 11830 |
| 15 | 23669 |
| 16 | 47347 |
| 17 | 94704 |
| 18 | 189419 |
| 19 | 378850 |
| 20 | 757713 |
| 21 | 1515440 |
| 22 | 3030895 |
| 23 | 6061806 |
| 24 | 12123629 |
| 25 | 24247276 |
| 26 | 48494571 |
| 27 | 96989162 |
| 28 | 193978345 |
| 29 | 387956712 |
| 30 | 775913447 |
| 31 | 1551826917 |
| 32 | 3103653858 |
[1,2,4,9,20,43,89,181,365,734,1473,2952,5911, 11830,23669,47347,94704,189419,378850,757713, 1515440,3030895,6061806,12123629,24247276, 48494571,96989162,193978345,387956712,775913447, 1551826917,3103653858] |