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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 5 |
| 3 | 11 |
| 4 | 47 |
| 5 | 143 |
| 6 | 577 |
| 7 | 2003 |
| 8 | 8189 |
| 9 | 29843 |
| 10 | 124237 |
| 11 | 467583 |
| 12 | 1960681 |
| 13 | 7577163 |
| 14 | 31962501 |
| 15 | 125734635 |
| 16 | 534229159 |
| 17 | 2128096227 |
| 18 | 9092397583 |
| 19 | 36615310761 |
| 20 | 157023171309 |
| 21 | 638232284475 |
| 22 | 2746009559707 |
| 23 | 11244568651801 |
| 24 | 48528835473245 |
| 25 | 199957782233787 |
| 26 | 865169500080713 |
| 27 | 3584439532293331 |
[1,1,5,11,47,143,577,2003,8189,29843,124237, 467583,1960681,7577163,31962501,125734635, 534229159,2128096227,9092397583,36615310761, 157023171309,638232284475,2746009559707, 11244568651801,48528835473245,199957782233787, 865169500080713,3584439532293331] |