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| n | a(n) |
|---|---|
| 1 | 5 |
| 2 | 21 |
| 3 | 33 |
| 4 | 141 |
| 5 | 610 |
| 6 | 2516 |
| 7 | 14294 |
| 8 | 88030 |
| 9 | 509381 |
| 10 | 3093005 |
| 11 | 19312237 |
| 12 | 118337189 |
| 13 | 727121421 |
| 14 | 4504400841 |
| 15 | 27814686154 |
| 16 | 171570763044 |
| 17 | 1060312932793 |
| 18 | 6551216623239 |
| 19 | 40456288742814 |
| 20 | 249917071426582 |
| 21 | 1543961418215996 |
[5,21,33,141,610,2516,14294,88030,509381,3093005, 19312237,118337189,727121421,4504400841, 27814686154,171570763044,1060312932793, 6551216623239,40456288742814,249917071426582, 1543961418215996] |