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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 7 |
| 4 | 25 |
| 5 | 73 |
| 6 | 281 |
| 7 | 925 |
| 8 | 3715 |
| 9 | 13163 |
| 10 | 54363 |
| 11 | 202455 |
| 12 | 852991 |
| 13 | 3292995 |
| 14 | 14084535 |
| 15 | 55873491 |
| 16 | 241813049 |
| 17 | 979932617 |
| 18 | 4281582977 |
| 19 | 17650788629 |
| 20 | 77729583213 |
| 21 | 324985250073 |
| 22 | 1440647882005 |
| 23 | 6094701870121 |
| 24 | 27170626608273 |
| 25 | 116101605411245 |
| 26 | 520124649045449 |
| 27 | 2241711086478733 |
| 28 | 10085665589693369 |
[1,1,3,7,25,73,281,925,3715,13163,54363,202455, 852991,3292995,14084535,55873491,241813049, 979932617,4281582977,17650788629,77729583213, 324985250073,1440647882005,6094701870121, 27170626608273,116101605411245,520124649045449, 2241711086478733,10085665589693369] |