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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 9 |
| 4 | 15 |
| 5 | 45 |
| 6 | 105 |
| 7 | 315 |
| 8 | 1155 |
| 9 | 7425 |
| 10 | 8415 |
| 11 | 8925 |
| 12 | 31815 |
| 13 | 32445 |
| 14 | 351351 |
| 15 | 442365 |
| 16 | 13800465 |
| 17 | 14571585 |
| 18 | 16286445 |
| 19 | 20355825 |
| 20 | 20487159 |
| 21 | 78524145 |
| 22 | 132701205 |
| 23 | 159030135 |
| 24 | 815634435 |
| 25 | 2586415095 |
| 26 | 29169504045 |
| 27 | 40833636525 |
| 28 | 125208115065 |
[1,3,9,15,45,105,315,1155,7425,8415,8925,31815, 32445,351351,442365,13800465,14571585,16286445, 20355825,20487159,78524145,132701205,159030135, 815634435,2586415095,29169504045,40833636525, 125208115065] |