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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 27 |
| 3 | 54 |
| 4 | 740 |
| 5 | 2827 |
| 6 | 3113 |
| 7 | 27008 |
| 8 | 71704 |
| 9 | 59070 |
| 10 | 408600 |
| 11 | 894812 |
| 12 | 621910 |
| 13 | 3704174 |
| 14 | 7087046 |
| 15 | 4373879 |
| 16 | 23558696 |
| 17 | 41171126 |
| 18 | 23396689 |
| 19 | 116650532 |
| 20 | 190010902 |
| 21 | 101247815 |
| 22 | 476808796 |
| 23 | 736407602 |
| 24 | 373431803 |
| 25 | 1678517670 |
| 26 | 2482516953 |
| 27 | 1208979602 |
| 28 | 5235742304 |
| 29 | 7477415626 |
[1,3,27,54,740,2827,3113,27008,71704,59070,408600, 894812,621910,3704174,7087046,4373879,23558696, 41171126,23396689,116650532,190010902,101247815, 476808796,736407602,373431803,1678517670, 2482516953,1208979602,5235742304,7477415626] |