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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 5 |
| 3 | 11 |
| 4 | 47 |
| 5 | 155 |
| 6 | 589 |
| 7 | 2243 |
| 8 | 8561 |
| 9 | 33467 |
| 10 | 133517 |
| 11 | 529315 |
| 12 | 2148221 |
| 13 | 8691577 |
| 14 | 35431673 |
| 15 | 145777825 |
| 16 | 600472755 |
| 17 | 2488691561 |
| 18 | 10353202637 |
| 19 | 43132961113 |
| 20 | 180596954251 |
| 21 | 757853615215 |
| 22 | 3188079252033 |
| 23 | 13450531998057 |
| 24 | 56826331572443 |
| 25 | 240626394752241 |
| 26 | 1021097344594587 |
| 27 | 4339536786320825 |
[1,1,5,11,47,155,589,2243,8561,33467,133517, 529315,2148221,8691577,35431673,145777825, 600472755,2488691561,10353202637,43132961113, 180596954251,757853615215,3188079252033, 13450531998057,56826331572443,240626394752241, 1021097344594587,4339536786320825] |