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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 8 |
| 4 | 23 |
| 5 | 67 |
| 6 | 197 |
| 7 | 582 |
| 8 | 1725 |
| 9 | 5124 |
| 10 | 15245 |
| 11 | 45412 |
| 12 | 135401 |
| 13 | 404015 |
| 14 | 1206247 |
| 15 | 3603230 |
| 16 | 10767855 |
| 17 | 32189931 |
| 18 | 96259221 |
| 19 | 287924196 |
| 20 | 861415809 |
| 21 | 2577711045 |
| 22 | 7714933851 |
| 23 | 23093949534 |
| 24 | 69139301043 |
| 25 | 207017139906 |
| 26 | 619921659303 |
| 27 | 1856572250112 |
[1,3,8,23,67,197,582,1725,5124,15245,45412,135401, 404015,1206247,3603230,10767855,32189931,96259221, 287924196,861415809,2577711045,7714933851, 23093949534,69139301043,207017139906,619921659303, 1856572250112] |