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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 5 |
| 3 | 12 |
| 4 | 317 |
| 5 | 646 |
| 6 | 1609 |
| 7 | 3864 |
| 8 | 102073 |
| 9 | 208010 |
| 10 | 518093 |
| 11 | 1244196 |
| 12 | 32867189 |
| 13 | 66978574 |
| 14 | 166824337 |
| 15 | 400627248 |
| 16 | 10583132785 |
| 17 | 21566892818 |
| 18 | 53716918421 |
| 19 | 129000729660 |
| 20 | 3407735889581 |
| 21 | 6944472508822 |
| 22 | 17296680907225 |
| 23 | 41537834323272 |
| 24 | 1097280373312297 |
[1,2,5,12,317,646,1609,3864,102073,208010,518093, 1244196,32867189,66978574,166824337,400627248, 10583132785,21566892818,53716918421,129000729660, 3407735889581,6944472508822,17296680907225, 41537834323272,1097280373312297] |