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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 5 |
| 3 | 9 |
| 4 | 45 |
| 5 | 109 |
| 6 | 497 |
| 7 | 1505 |
| 8 | 6133 |
| 9 | 21789 |
| 10 | 82533 |
| 11 | 321777 |
| 12 | 1194945 |
| 13 | 4811085 |
| 14 | 18219585 |
| 15 | 73076577 |
| 16 | 286306473 |
| 17 | 1134972601 |
| 18 | 4568099273 |
| 19 | 18063724073 |
| 20 | 73541366101 |
| 21 | 293534062209 |
| 22 | 1194924730629 |
| 23 | 4838269689497 |
| 24 | 19642019715565 |
| 25 | 80442812392417 |
| 26 | 326934305905229 |
| 27 | 1345821122024457 |
| 28 | 5501463899445453 |
[1,1,5,9,45,109,497,1505,6133,21789,82533,321777, 1194945,4811085,18219585,73076577,286306473, 1134972601,4568099273,18063724073,73541366101, 293534062209,1194924730629,4838269689497, 19642019715565,80442812392417,326934305905229, 1345821122024457,5501463899445453] |