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| n | a(n) |
|---|---|
| 1 | 9 |
| 2 | 15 |
| 3 | 87 |
| 4 | 205 |
| 5 | 899 |
| 6 | 2521 |
| 7 | 9709 |
| 8 | 29747 |
| 9 | 107261 |
| 10 | 344055 |
| 11 | 1199763 |
| 12 | 3940341 |
| 13 | 13507819 |
| 14 | 44905025 |
| 15 | 152598957 |
| 16 | 510467683 |
| 17 | 1726955485 |
| 18 | 5795447559 |
| 19 | 19561570195 |
| 20 | 65753998917 |
| 21 | 221680877531 |
| 22 | 745782497713 |
| 23 | 2512791313869 |
| 24 | 8457223721011 |
[9,15,87,205,899,2521,9709,29747,107261,344055, 1199763,3940341,13507819,44905025,152598957, 510467683,1726955485,5795447559,19561570195, 65753998917,221680877531,745782497713, 2512791313869,8457223721011] |