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| n | a(n) |
|---|---|
| 1 | 3 |
| 2 | 6 |
| 3 | 27 |
| 4 | 120 |
| 5 | 600 |
| 6 | 3078 |
| 7 | 16611 |
| 8 | 91872 |
| 9 | 520749 |
| 10 | 3004200 |
| 11 | 17594247 |
| 12 | 104304888 |
| 13 | 624801957 |
| 14 | 3775722342 |
| 15 | 22991161500 |
| 16 | 140928011136 |
| 17 | 868886416866 |
| 18 | 5384796881850 |
| 19 | 33525472069563 |
| 20 | 209592223788000 |
| 21 | 1315211209630794 |
| 22 | 8281053081282894 |
| 23 | 52301607644921259 |
| 24 | 331260902534858976 |
| 25 | 2103541885645955625 |
| 26 | 13389670112374830378 |
[3,6,27,120,600,3078,16611,91872,520749,3004200, 17594247,104304888,624801957,3775722342, 22991161500,140928011136,868886416866, 5384796881850,33525472069563,209592223788000, 1315211209630794,8281053081282894, 52301607644921259,331260902534858976, 2103541885645955625,13389670112374830378] |