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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 3 |
| 4 | 11 |
| 5 | 43 |
| 6 | 181 |
| 7 | 799 |
| 8 | 3641 |
| 9 | 17013 |
| 10 | 81069 |
| 11 | 392427 |
| 12 | 1924363 |
| 13 | 9539431 |
| 14 | 47726001 |
| 15 | 240671423 |
| 16 | 1222026809 |
| 17 | 6242470529 |
| 18 | 32058889049 |
| 19 | 165425745315 |
| 20 | 857247711523 |
| 21 | 4459393489451 |
| 22 | 23278491380285 |
| 23 | 121901175460639 |
| 24 | 640201825131969 |
[1,1,3,11,43,181,799,3641,17013,81069,392427, 1924363,9539431,47726001,240671423,1222026809, 6242470529,32058889049,165425745315,857247711523, 4459393489451,23278491380285,121901175460639, 640201825131969] |