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| n | a(n) |
|---|---|
| 1 | 31 |
| 2 | 961 |
| 3 | 6115 |
| 4 | 23071 |
| 5 | 65955 |
| 6 | 158217 |
| 7 | 335915 |
| 8 | 651531 |
| 9 | 1178343 |
| 10 | 2015377 |
| 11 | 3292963 |
| 12 | 5178919 |
| 13 | 7885387 |
| 14 | 11676345 |
| 15 | 16875819 |
| 16 | 23876819 |
| 17 | 33151023 |
| 18 | 45259233 |
| 19 | 60862627 |
| 20 | 80734831 |
| 21 | 105774835 |
| 22 | 137020777 |
| 23 | 175664619 |
| 24 | 223067739 |
| 25 | 280777463 |
| 26 | 350544561 |
[31,961,6115,23071,65955,158217,335915,651531, 1178343,2015377,3292963,5178919,7885387,11676345, 16875819,23876819,33151023,45259233,60862627, 80734831,105774835,137020777,175664619,223067739, 280777463,350544561] |