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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 3 |
| 4 | 7 |
| 5 | 13 |
| 6 | 33 |
| 7 | 91 |
| 8 | 223 |
| 9 | 597 |
| 10 | 1753 |
| 11 | 4963 |
| 12 | 14391 |
| 13 | 44413 |
| 14 | 137137 |
| 15 | 427083 |
| 16 | 1382383 |
| 17 | 4534981 |
| 18 | 14981673 |
| 19 | 50719507 |
| 20 | 174494983 |
| 21 | 605276973 |
| 22 | 2135204161 |
| 23 | 7647369403 |
| 24 | 27643067007 |
| 25 | 101211363253 |
| 26 | 375548195833 |
| 27 | 1406858084931 |
| 28 | 5326762882903 |
| 29 | 20403498329437 |
[1,1,1,3,7,13,33,91,223,597,1753,4963,14391,44413, 137137,427083,1382383,4534981,14981673,50719507, 174494983,605276973,2135204161,7647369403, 27643067007,101211363253,375548195833, 1406858084931,5326762882903,20403498329437] |