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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 7 |
| 4 | 21 |
| 5 | 57 |
| 6 | 182 |
| 7 | 565 |
| 8 | 1931 |
| 9 | 6670 |
| 10 | 24537 |
| 11 | 92337 |
| 12 | 364602 |
| 13 | 1477148 |
| 14 | 6219031 |
| 15 | 26875932 |
| 16 | 119930947 |
| 17 | 548688443 |
| 18 | 2580814003 |
| 19 | 12425175838 |
| 20 | 61302331782 |
| 21 | 309055818656 |
| 22 | 1592723862598 |
| 23 | 8374123173858 |
| 24 | 44917765035082 |
| 25 | 245452258746785 |
| 26 | 1366116578058731 |
| 27 | 7736098938006873 |
| 28 | 44558958700083896 |
[1,3,7,21,57,182,565,1931,6670,24537,92337,364602, 1477148,6219031,26875932,119930947,548688443, 2580814003,12425175838,61302331782,309055818656, 1592723862598,8374123173858,44917765035082, 245452258746785,1366116578058731,7736098938006873, 44558958700083896] |