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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 7 |
| 3 | 27 |
| 4 | 107 |
| 5 | 470 |
| 6 | 2033 |
| 7 | 9086 |
| 8 | 41227 |
| 9 | 188036 |
| 10 | 872685 |
| 11 | 4059101 |
| 12 | 19039409 |
| 13 | 89808886 |
| 14 | 424989379 |
| 15 | 2022124509 |
| 16 | 9644549971 |
| 17 | 46156345590 |
| 18 | 221518673285 |
| 19 | 1065265253809 |
| 20 | 5135590502267 |
| 21 | 24800865960620 |
| 22 | 119981448823525 |
| 23 | 581410944356560 |
| 24 | 2821159938426259 |
| 25 | 13708276145589738 |
| 26 | 66688481480233137 |
[1,2,7,27,107,470,2033,9086,41227,188036,872685, 4059101,19039409,89808886,424989379,2022124509, 9644549971,46156345590,221518673285,1065265253809, 5135590502267,24800865960620,119981448823525, 581410944356560,2821159938426259, 13708276145589738,66688481480233137] |