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| n | a(n) |
|---|---|
| 1 | 174 |
| 2 | 726 |
| 3 | 3030 |
| 4 | 12630 |
| 5 | 52662 |
| 6 | 219606 |
| 7 | 915702 |
| 8 | 3818262 |
| 9 | 15921462 |
| 10 | 66389334 |
| 11 | 276830070 |
| 12 | 1154326422 |
| 13 | 4813311414 |
| 14 | 20070547926 |
| 15 | 83690183670 |
| 16 | 348971383830 |
| 17 | 1455141093942 |
| 18 | 6067648253526 |
| 19 | 25300883554422 |
| 20 | 105499640297622 |
[174,726,3030,12630,52662,219606,915702,3818262, 15921462,66389334,276830070,1154326422,4813311414, 20070547926,83690183670,348971383830, 1455141093942,6067648253526,25300883554422, 105499640297622] |