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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 5 |
| 3 | 19 |
| 4 | 87 |
| 5 | 363 |
| 6 | 1735 |
| 7 | 7717 |
| 8 | 37377 |
| 9 | 172405 |
| 10 | 842961 |
| 11 | 3969177 |
| 12 | 19518485 |
| 13 | 93212797 |
| 14 | 460143557 |
| 15 | 2218880423 |
| 16 | 10983882619 |
| 17 | 53341437199 |
| 18 | 264580362679 |
| 19 | 1291708896727 |
| 20 | 6416774513695 |
| 21 | 31454760994923 |
| 22 | 156438640458835 |
| 23 | 769300039796771 |
| 24 | 3829561705630703 |
| 25 | 18879985489563915 |
| 26 | 94052258269651535 |
[1,1,5,19,87,363,1735,7717,37377,172405,842961, 3969177,19518485,93212797,460143557,2218880423, 10983882619,53341437199,264580362679, 1291708896727,6416774513695,31454760994923, 156438640458835,769300039796771,3829561705630703, 18879985489563915,94052258269651535] |