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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 5 |
| 3 | 14 |
| 4 | 47 |
| 5 | 149 |
| 6 | 481 |
| 7 | 1544 |
| 8 | 4965 |
| 9 | 15957 |
| 10 | 51293 |
| 11 | 164870 |
| 12 | 529947 |
| 13 | 1703417 |
| 14 | 5475329 |
| 15 | 17599456 |
| 16 | 56570281 |
| 17 | 181834969 |
| 18 | 584475733 |
| 19 | 1878691886 |
| 20 | 6038716423 |
| 21 | 19410365421 |
| 22 | 62391120801 |
| 23 | 200545011400 |
| 24 | 644615789581 |
| 25 | 2072001259341 |
| 26 | 6660074556205 |
[1,5,14,47,149,481,1544,4965,15957,51293,164870, 529947,1703417,5475329,17599456,56570281, 181834969,584475733,1878691886,6038716423, 19410365421,62391120801,200545011400,644615789581, 2072001259341,6660074556205] |