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| n | a(n) |
|---|---|
| 1 | 8 |
| 2 | 20 |
| 3 | 48 |
| 4 | 118 |
| 5 | 306 |
| 6 | 838 |
| 7 | 2372 |
| 8 | 6886 |
| 9 | 20244 |
| 10 | 60022 |
| 11 | 178830 |
| 12 | 534358 |
| 13 | 1599374 |
| 14 | 4791718 |
| 15 | 14364057 |
| 16 | 43072966 |
| 17 | 129185618 |
| 18 | 387499222 |
| 19 | 1162397834 |
| 20 | 3487020598 |
| 21 | 10460762306 |
| 22 | 31381768198 |
| 23 | 94144406138 |
| 24 | 282431662246 |
| 25 | 847292291373 |
| 26 | 2541872205622 |
| 27 | 7625608530780 |
| 28 | 22876811586838 |
| 29 | 68630410502264 |
[8,20,48,118,306,838,2372,6886,20244,60022,178830, 534358,1599374,4791718,14364057,43072966, 129185618,387499222,1162397834,3487020598, 10460762306,31381768198,94144406138,282431662246, 847292291373,2541872205622,7625608530780, 22876811586838,68630410502264] |