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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 5 |
| 2 | 17 |
| 3 | 71 |
| 4 | 289 |
| 5 | 1192 |
| 6 | 4913 |
| 7 | 20257 |
| 8 | 83521 |
| 9 | 344366 |
| 10 | 1419857 |
| 11 | 5854221 |
| 12 | 24137569 |
| 13 | 99521747 |
| 14 | 410338673 |
| 15 | 1691869692 |
| 16 | 6975757441 |
| 17 | 28761784748 |
| 18 | 118587876497 |
| 19 | 488950340715 |
| 20 | 2015993900449 |
| 21 | 8312155792153 |
[1,5,17,71,289,1192,4913,20257,83521,344366, 1419857,5854221,24137569,99521747,410338673, 1691869692,6975757441,28761784748,118587876497, 488950340715,2015993900449,8312155792153] |