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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 9 |
| 3 | 33 |
| 4 | 113 |
| 5 | 593 |
| 6 | 2435 |
| 7 | 10317 |
| 8 | 45615 |
| 9 | 195093 |
| 10 | 841571 |
| 11 | 3646693 |
| 12 | 15718319 |
| 13 | 67872219 |
| 14 | 293228491 |
| 15 | 1265855985 |
| 16 | 5466238427 |
| 17 | 23604968149 |
| 18 | 101924529475 |
| 19 | 440126714041 |
| 20 | 1900525775017 |
| 21 | 8206607484875 |
| 22 | 35437081228013 |
| 23 | 153021248588503 |
[1,9,33,113,593,2435,10317,45615,195093,841571, 3646693,15718319,67872219,293228491,1265855985, 5466238427,23604968149,101924529475,440126714041, 1900525775017,8206607484875,35437081228013, 153021248588503] |