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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 5 |
| 2 | 17 |
| 3 | 43 |
| 4 | 97 |
| 5 | 211 |
| 6 | 457 |
| 7 | 995 |
| 8 | 2177 |
| 9 | 4771 |
| 10 | 10441 |
| 11 | 22771 |
| 12 | 49441 |
| 13 | 106835 |
| 14 | 229769 |
| 15 | 491971 |
| 16 | 1049089 |
| 17 | 2228803 |
| 18 | 4719241 |
| 19 | 9962195 |
| 20 | 20972321 |
| 21 | 44041075 |
| 22 | 92275657 |
| 23 | 192939043 |
| 24 | 402654337 |
| 25 | 838862051 |
| 26 | 1744831817 |
| 27 | 3623880115 |
| 28 | 7516194337 |
[1,5,17,43,97,211,457,995,2177,4771,10441,22771, 49441,106835,229769,491971,1049089,2228803, 4719241,9962195,20972321,44041075,92275657, 192939043,402654337,838862051,1744831817, 3623880115,7516194337] |