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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 7 |
| 4 | 21 |
| 5 | 61 |
| 6 | 183 |
| 7 | 547 |
| 8 | 1641 |
| 9 | 4921 |
| 10 | 14763 |
| 11 | 44287 |
| 12 | 132861 |
| 13 | 398581 |
| 14 | 1195743 |
| 15 | 3587227 |
| 16 | 10761681 |
| 17 | 32285041 |
| 18 | 96855123 |
| 19 | 290565367 |
| 20 | 871696101 |
| 21 | 2615088301 |
| 22 | 7845264903 |
| 23 | 23535794707 |
| 24 | 70607384121 |
| 25 | 211822152361 |
| 26 | 635466457083 |
[1,1,3,7,21,61,183,547,1641,4921,14763,44287, 132861,398581,1195743,3587227,10761681,32285041, 96855123,290565367,871696101,2615088301, 7845264903,23535794707,70607384121,211822152361, 635466457083] |