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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 5 |
| 3 | 17 |
| 4 | 71 |
| 5 | 297 |
| 6 | 1299 |
| 7 | 5699 |
| 8 | 25707 |
| 9 | 116793 |
| 10 | 536131 |
| 11 | 2480397 |
| 12 | 11559489 |
| 13 | 54122031 |
| 14 | 254694451 |
| 15 | 1203531177 |
| 16 | 5706949229 |
| 17 | 27145042957 |
| 18 | 129487009863 |
| 19 | 619188068719 |
| 20 | 2967426010429 |
| 21 | 14250219049149 |
| 22 | 68558210262343 |
| 23 | 330381620037843 |
| 24 | 1594552192024995 |
| 25 | 7706792146786665 |
| 26 | 37296631154429987 |
| 27 | 180711774104487389 |
[1,1,5,17,71,297,1299,5699,25707,116793,536131, 2480397,11559489,54122031,254694451,1203531177, 5706949229,27145042957,129487009863,619188068719, 2967426010429,14250219049149,68558210262343, 330381620037843,1594552192024995,7706792146786665, 37296631154429987,180711774104487389] |