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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 5 |
| 3 | 19 |
| 4 | 74 |
| 5 | 298 |
| 6 | 1281 |
| 7 | 5462 |
| 8 | 24099 |
| 9 | 108077 |
| 10 | 487391 |
| 11 | 2236789 |
| 12 | 10301023 |
| 13 | 47843041 |
| 14 | 223735126 |
| 15 | 1049895022 |
| 16 | 4956915448 |
| 17 | 23474704967 |
| 18 | 111584020732 |
| 19 | 532185167879 |
| 20 | 2544210999914 |
| 21 | 12197908389471 |
| 22 | 58601743861377 |
| 23 | 282127456392257 |
| 24 | 1360861827426384 |
| 25 | 6574796619320823 |
| 26 | 31817366089923143 |
| 27 | 154187495072008827 |
[1,2,5,19,74,298,1281,5462,24099,108077,487391, 2236789,10301023,47843041,223735126,1049895022, 4956915448,23474704967,111584020732,532185167879, 2544210999914,12197908389471,58601743861377, 282127456392257,1360861827426384,6574796619320823, 31817366089923143,154187495072008827] |