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| n | a(n) |
|---|---|
| 1 | 8 |
| 2 | 24 |
| 3 | 30 |
| 4 | 90 |
| 5 | 231 |
| 6 | 631 |
| 7 | 1586 |
| 8 | 4230 |
| 9 | 11059 |
| 10 | 29053 |
| 11 | 75910 |
| 12 | 199512 |
| 13 | 522870 |
| 14 | 1370889 |
| 15 | 3593603 |
| 16 | 9425485 |
| 17 | 24711611 |
| 18 | 64792085 |
| 19 | 169885855 |
| 20 | 445461189 |
| 21 | 1167988296 |
| 22 | 3062473985 |
| 23 | 8029902757 |
| 24 | 21054655960 |
| 25 | 55205582288 |
| 26 | 144750167082 |
| 27 | 379538412292 |
[8,24,30,90,231,631,1586,4230,11059,29053,75910, 199512,522870,1370889,3593603,9425485,24711611, 64792085,169885855,445461189,1167988296, 3062473985,8029902757,21054655960,55205582288, 144750167082,379538412292] |