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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 9 |
| 4 | 32 |
| 5 | 107 |
| 6 | 411 |
| 7 | 1553 |
| 8 | 6194 |
| 9 | 24389 |
| 10 | 100612 |
| 11 | 412488 |
| 12 | 1734453 |
| 13 | 7264212 |
| 14 | 31092761 |
| 15 | 132827500 |
| 16 | 575349257 |
| 17 | 2489633556 |
| 18 | 10903009511 |
| 19 | 47736774170 |
| 20 | 210767379271 |
| 21 | 930722838057 |
| 22 | 4140160460869 |
| 23 | 18425314173567 |
| 24 | 82449058082568 |
| 25 | 369170820588110 |
| 26 | 1660949457878375 |
| 27 | 7478371588472407 |
| 28 | 33798023245901890 |
[1,1,3,9,32,107,411,1553,6194,24389,100612,412488, 1734453,7264212,31092761,132827500,575349257, 2489633556,10903009511,47736774170,210767379271, 930722838057,4140160460869,18425314173567, 82449058082568,369170820588110,1660949457878375, 7478371588472407,33798023245901890] |