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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 5 |
| 3 | 17 |
| 4 | 57 |
| 5 | 129 |
| 6 | 433 |
| 7 | 1009 |
| 8 | 3089 |
| 9 | 7697 |
| 10 | 20049 |
| 11 | 48849 |
| 12 | 139729 |
| 13 | 317137 |
| 14 | 818897 |
| 15 | 2040017 |
| 16 | 5125329 |
| 17 | 12000465 |
| 18 | 30811345 |
| 19 | 71582929 |
| 20 | 179008721 |
| 21 | 427693265 |
| 22 | 1024611537 |
| 23 | 2413499601 |
| 24 | 6027416785 |
| 25 | 13788615889 |
[1,5,17,57,129,433,1009,3089,7697,20049,48849, 139729,317137,818897,2040017,5125329,12000465, 30811345,71582929,179008721,427693265,1024611537, 2413499601,6027416785,13788615889] |