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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 11 |
| 3 | 43 |
| 4 | 231 |
| 5 | 1337 |
| 6 | 9739 |
| 7 | 76209 |
| 8 | 706109 |
| 9 | 6914977 |
| 10 | 78150249 |
| 11 | 920172983 |
| 12 | 12216376453 |
| 13 | 168531536319 |
| 14 | 2571960399839 |
| 15 | 40581616143967 |
| 16 | 701349512411763 |
| 17 | 12460393480873445 |
| 18 | 240094506439569631 |
| 19 | 4749510978132662277 |
[1,3,11,43,231,1337,9739,76209,706109,6914977, 78150249,920172983,12216376453,168531536319, 2571960399839,40581616143967,701349512411763, 12460393480873445,240094506439569631, 4749510978132662277] |