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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 13 |
| 4 | 67 |
| 5 | 369 |
| 6 | 2083 |
| 7 | 11869 |
| 8 | 67875 |
| 9 | 388705 |
| 10 | 2227267 |
| 11 | 12764973 |
| 12 | 73165315 |
| 13 | 419377873 |
| 14 | 2403873891 |
| 15 | 13779078781 |
| 16 | 78982269667 |
| 17 | 452730133185 |
| 18 | 2595071559811 |
| 19 | 14875080747085 |
| 20 | 85264715699139 |
| 21 | 488741675881009 |
| 22 | 2801492102959267 |
| 23 | 16058295037221021 |
| 24 | 92046962959297699 |
[1,3,13,67,369,2083,11869,67875,388705,2227267, 12764973,73165315,419377873,2403873891, 13779078781,78982269667,452730133185, 2595071559811,14875080747085,85264715699139, 488741675881009,2801492102959267, 16058295037221021,92046962959297699] |