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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 4097 |
| 3 | 535538 |
| 4 | 17312754 |
| 5 | 261453379 |
| 6 | 2438235715 |
| 7 | 16279522916 |
| 8 | 84998999652 |
| 9 | 367428536133 |
| 10 | 1367428536133 |
| 11 | 4505856912854 |
| 12 | 13421957361110 |
| 13 | 36720042483591 |
| 14 | 93413954858887 |
| 15 | 223160292749512 |
| 16 | 504635269460168 |
| 17 | 1087257506689929 |
| 18 | 2244088888116105 |
| 19 | 4457403807182266 |
[0,1,4097,535538,17312754,261453379,2438235715, 16279522916,84998999652,367428536133, 1367428536133,4505856912854,13421957361110, 36720042483591,93413954858887,223160292749512, 504635269460168,1087257506689929,2244088888116105, 4457403807182266] |