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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 7 |
| 4 | 27 |
| 5 | 87 |
| 6 | 361 |
| 7 | 1319 |
| 8 | 5715 |
| 9 | 22521 |
| 10 | 100367 |
| 11 | 415235 |
| 12 | 1886385 |
| 13 | 8073371 |
| 14 | 37195897 |
| 15 | 163184991 |
| 16 | 759886449 |
| 17 | 3397005989 |
| 18 | 15951150479 |
| 19 | 72362430593 |
| 20 | 342075234779 |
| 21 | 1570128725741 |
| 22 | 7463295523933 |
| 23 | 34585271828523 |
| 24 | 165148822870611 |
| 25 | 771377322247203 |
| 26 | 3697702453493303 |
| 27 | 17386020857727765 |
| 28 | 83618609128148883 |
[1,1,3,7,27,87,361,1319,5715,22521,100367,415235, 1886385,8073371,37195897,163184991,759886449, 3397005989,15951150479,72362430593,342075234779, 1570128725741,7463295523933,34585271828523, 165148822870611,771377322247203,3697702453493303, 17386020857727765,83618609128148883] |