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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 13 |
| 3 | 53 |
| 4 | 251 |
| 5 | 1123 |
| 6 | 5443 |
| 7 | 25319 |
| 8 | 124085 |
| 9 | 589525 |
| 10 | 2907101 |
| 11 | 13992377 |
| 12 | 69260281 |
| 13 | 336246069 |
| 14 | 1668515057 |
| 15 | 8149453349 |
| 16 | 40508704195 |
| 17 | 198730129755 |
| 18 | 989055732315 |
| 19 | 4868337933007 |
| 20 | 24251331823247 |
| 21 | 119677240767379 |
| 22 | 596579249085239 |
| 23 | 2950013134883235 |
| 24 | 14713426845193475 |
| 25 | 72874410714058567 |
| 26 | 363620465475437771 |
[1,3,13,53,251,1123,5443,25319,124085,589525, 2907101,13992377,69260281,336246069,1668515057, 8149453349,40508704195,198730129755,989055732315, 4868337933007,24251331823247,119677240767379, 596579249085239,2950013134883235, 14713426845193475,72874410714058567, 363620465475437771] |