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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 11 |
| 3 | 47 |
| 4 | 205 |
| 5 | 927 |
| 6 | 4263 |
| 7 | 19873 |
| 8 | 93477 |
| 9 | 443099 |
| 10 | 2111677 |
| 11 | 10111271 |
| 12 | 48593723 |
| 13 | 234274543 |
| 14 | 1132435961 |
| 15 | 5486484089 |
| 16 | 26633535227 |
| 17 | 129513967703 |
| 18 | 630765345243 |
| 19 | 3076177529709 |
| 20 | 15020545826403 |
| 21 | 73424228430541 |
| 22 | 359275730715121 |
| 23 | 1759596267979597 |
| 24 | 8625046993876771 |
| 25 | 42310103527742087 |
| 26 | 207699373802231315 |
[1,3,11,47,205,927,4263,19873,93477,443099, 2111677,10111271,48593723,234274543,1132435961, 5486484089,26633535227,129513967703,630765345243, 3076177529709,15020545826403,73424228430541, 359275730715121,1759596267979597,8625046993876771, 42310103527742087,207699373802231315] |