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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 8 |
| 3 | 38 |
| 4 | 167 |
| 5 | 681 |
| 6 | 2864 |
| 7 | 12148 |
| 8 | 51480 |
| 9 | 217587 |
| 10 | 919656 |
| 11 | 3889592 |
| 12 | 16451263 |
| 13 | 69570928 |
| 14 | 294209541 |
| 15 | 1244221402 |
| 16 | 5261851987 |
| 17 | 22252448435 |
| 18 | 94105875249 |
| 19 | 397975165117 |
| 20 | 1683043391582 |
| 21 | 7117616634217 |
| 22 | 30100509329656 |
| 23 | 127295517065791 |
[1,8,38,167,681,2864,12148,51480,217587,919656, 3889592,16451263,69570928,294209541,1244221402, 5261851987,22252448435,94105875249,397975165117, 1683043391582,7117616634217,30100509329656, 127295517065791] |