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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 7 |
| 3 | 21 |
| 4 | 89 |
| 5 | 393 |
| 6 | 2225 |
| 7 | 18609 |
| 8 | 101057 |
| 9 | 816993 |
| 10 | 13457825 |
| 11 | 51228609 |
| 12 | 810315137 |
| 13 | 17176207233 |
| 14 | 131372857985 |
| 15 | 1305079808769 |
| 16 | 26689011214337 |
| 17 | 589160232591873 |
| 18 | 8710689840914945 |
| 19 | 54912598925708289 |
| 20 | 1233406496755480577 |
| 21 | 66645549104613373953 |
| 22 | 1133684888589441378305 |
| 23 | 7520981752666086084609 |
| 24 | 200384978441063958102017 |
[1,3,7,21,89,393,2225,18609,101057,816993, 13457825,51228609,810315137,17176207233, 131372857985,1305079808769,26689011214337, 589160232591873,8710689840914945, 54912598925708289,1233406496755480577, 66645549104613373953,1133684888589441378305, 7520981752666086084609,200384978441063958102017] |