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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 12 |
| 3 | 54 |
| 4 | 216 |
| 5 | 810 |
| 6 | 2916 |
| 7 | 10206 |
| 8 | 34992 |
| 9 | 118098 |
| 10 | 393660 |
| 11 | 1299078 |
| 12 | 4251528 |
| 13 | 13817466 |
| 14 | 44641044 |
| 15 | 143489070 |
| 16 | 459165024 |
| 17 | 1463588514 |
| 18 | 4649045868 |
| 19 | 14721978582 |
| 20 | 46490458680 |
| 21 | 146444944842 |
| 22 | 460255540932 |
| 23 | 1443528742014 |
| 24 | 4518872583696 |
| 25 | 14121476824050 |
| 26 | 44059007691036 |
[2,12,54,216,810,2916,10206,34992,118098,393660, 1299078,4251528,13817466,44641044,143489070, 459165024,1463588514,4649045868,14721978582, 46490458680,146444944842,460255540932, 1443528742014,4518872583696,14121476824050, 44059007691036] |