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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 6 |
| 4 | 12 |
| 5 | 25 |
| 6 | 48 |
| 7 | 98 |
| 8 | 200 |
| 9 | 396 |
| 10 | 790 |
| 11 | 1584 |
| 12 | 3168 |
| 13 | 6331 |
| 14 | 12670 |
| 15 | 25335 |
| 16 | 50672 |
| 17 | 101354 |
| 18 | 202698 |
| 19 | 405403 |
| 20 | 810800 |
| 21 | 1621599 |
| 22 | 3243196 |
| 23 | 6486391 |
| 24 | 12972792 |
| 25 | 25945575 |
| 26 | 51891164 |
| 27 | 103782330 |
| 28 | 207564644 |
| 29 | 415129287 |
| 30 | 830258580 |
| 31 | 1660517170 |
| 32 | 3321034336 |
[1,2,6,12,25,48,98,200,396,790,1584,3168,6331, 12670,25335,50672,101354,202698,405403,810800, 1621599,3243196,6486391,12972792,25945575, 51891164,103782330,207564644,415129287,830258580, 1660517170,3321034336] |