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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 5 |
| 3 | 19 |
| 4 | 71 |
| 5 | 289 |
| 6 | 1223 |
| 7 | 5203 |
| 8 | 22415 |
| 9 | 97869 |
| 10 | 431155 |
| 11 | 1911777 |
| 12 | 8534569 |
| 13 | 38305925 |
| 14 | 172641851 |
| 15 | 781231793 |
| 16 | 3548304153 |
| 17 | 16165900741 |
| 18 | 73854023197 |
| 19 | 338260967667 |
| 20 | 1552835791277 |
| 21 | 7143364707329 |
| 22 | 32923999090571 |
| 23 | 152014881331641 |
| 24 | 703007464681223 |
| 25 | 3255996384526583 |
| 26 | 15101293781071973 |
| 27 | 70130698637215877 |
[1,1,5,19,71,289,1223,5203,22415,97869,431155, 1911777,8534569,38305925,172641851,781231793, 3548304153,16165900741,73854023197,338260967667, 1552835791277,7143364707329,32923999090571, 152014881331641,703007464681223,3255996384526583, 15101293781071973,70130698637215877] |