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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 5 |
| 3 | 19 |
| 4 | 49 |
| 5 | 126 |
| 6 | 469 |
| 7 | 1177 |
| 8 | 2881 |
| 9 | 6481 |
| 10 | 23101 |
| 11 | 53725 |
| 12 | 127153 |
| 13 | 274288 |
| 14 | 581925 |
| 15 | 1860751 |
| 16 | 4155649 |
| 17 | 9279791 |
| 18 | 19409221 |
| 19 | 39839239 |
| 20 | 77052401 |
| 21 | 229393207 |
| 22 | 481747949 |
| 23 | 1035561408 |
| 24 | 2082441025 |
| 25 | 4153434376 |
| 26 | 7822058869 |
| 27 | 14686515649 |
| 28 | 39394280689 |
| 29 | 79657493191 |
| 30 | 163600884901 |
[1,2,5,19,49,126,469,1177,2881,6481,23101,53725, 127153,274288,581925,1860751,4155649,9279791, 19409221,39839239,77052401,229393207,481747949, 1035561408,2082441025,4153434376,7822058869, 14686515649,39394280689,79657493191,163600884901] |