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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 9 |
| 3 | 38 |
| 4 | 173 |
| 5 | 811 |
| 6 | 3849 |
| 7 | 18466 |
| 8 | 89607 |
| 9 | 436576 |
| 10 | 2136997 |
| 11 | 10505680 |
| 12 | 51760229 |
| 13 | 255580298 |
| 14 | 1264625226 |
| 15 | 6265229147 |
| 16 | 31076772966 |
| 17 | 154320198127 |
| 18 | 766900717629 |
| 19 | 3813872974918 |
| 20 | 18979320285386 |
| 21 | 94494410482769 |
| 22 | 470682057046603 |
| 23 | 2345467942988451 |
| 24 | 11691550126914933 |
| 25 | 58296753148994862 |
| 26 | 290760597805640268 |
[1,2,9,38,173,811,3849,18466,89607,436576,2136997, 10505680,51760229,255580298,1264625226,6265229147, 31076772966,154320198127,766900717629, 3813872974918,18979320285386,94494410482769, 470682057046603,2345467942988451, 11691550126914933,58296753148994862, 290760597805640268] |