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| n | a(n) |
|---|---|
| 1 | 6 |
| 2 | 34 |
| 3 | 132 |
| 4 | 396 |
| 5 | 1264 |
| 6 | 3962 |
| 7 | 11886 |
| 8 | 35914 |
| 9 | 108556 |
| 10 | 325668 |
| 11 | 976552 |
| 12 | 2931922 |
| 13 | 8795766 |
| 14 | 26370674 |
| 15 | 79104084 |
| 16 | 237312252 |
| 17 | 711756448 |
| 18 | 2135076202 |
| 19 | 6405228606 |
| 20 | 19214238554 |
| 21 | 57640739420 |
| 22 | 172922218260 |
| 23 | 518757049560 |
| 24 | 1556255741762 |
| 25 | 4668767225286 |
[6,34,132,396,1264,3962,11886,35914,108556,325668, 976552,2931922,8795766,26370674,79104084, 237312252,711756448,2135076202,6405228606, 19214238554,57640739420,172922218260,518757049560, 1556255741762,4668767225286] |