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| n | a(n) |
|---|---|
| 1 | 6 |
| 2 | 514 |
| 3 | 9480 |
| 4 | 82398 |
| 5 | 457366 |
| 6 | 1886948 |
| 7 | 6308960 |
| 8 | 18038628 |
| 9 | 45704886 |
| 10 | 105193902 |
| 11 | 223903240 |
| 12 | 446650386 |
| 13 | 843619686 |
| 14 | 1520772064 |
| 15 | 2633182208 |
| 16 | 4401808232 |
| 17 | 7134239142 |
| 18 | 11250005754 |
| 19 | 17311081032 |
| 20 | 26058236134 |
| 21 | 38453958774 |
| 22 | 55732680828 |
[6,514,9480,82398,457366,1886948,6308960,18038628, 45704886,105193902,223903240,446650386,843619686, 1520772064,2633182208,4401808232,7134239142, 11250005754,17311081032,26058236134,38453958774, 55732680828] |