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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 9 |
| 4 | 32 |
| 5 | 112 |
| 6 | 419 |
| 7 | 1556 |
| 8 | 5966 |
| 9 | 22800 |
| 10 | 88624 |
| 11 | 343953 |
| 12 | 1348203 |
| 13 | 5280871 |
| 14 | 20811229 |
| 15 | 81995438 |
| 16 | 324318955 |
| 17 | 1282789042 |
| 18 | 5086938010 |
| 19 | 20174850237 |
| 20 | 80153717254 |
| 21 | 318501840735 |
| 22 | 1267153768678 |
| 23 | 5042296615421 |
| 24 | 20081851469220 |
| 25 | 79994363147594 |
| 26 | 318851212604716 |
| 27 | 1271134164676675 |
| 28 | 5069865013260048 |
[1,1,3,9,32,112,419,1556,5966,22800,88624,343953, 1348203,5280871,20811229,81995438,324318955, 1282789042,5086938010,20174850237,80153717254, 318501840735,1267153768678,5042296615421, 20081851469220,79994363147594,318851212604716, 1271134164676675,5069865013260048] |