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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 3 |
| 3 | 5 |
| 4 | 11 |
| 5 | 33 |
| 6 | 125 |
| 7 | 551 |
| 8 | 2695 |
| 9 | 14258 |
| 10 | 80343 |
| 11 | 477161 |
| 12 | 2964299 |
| 13 | 19155014 |
| 14 | 128203704 |
| 15 | 885830074 |
| 16 | 6302476880 |
| 17 | 46077527307 |
| 18 | 345590801495 |
| 19 | 2655466079629 |
| 20 | 20880388012659 |
| 21 | 167861200630015 |
| 22 | 1378589193074514 |
| 23 | 11558511053625488 |
[1,2,3,5,11,33,125,551,2695,14258,80343,477161, 2964299,19155014,128203704,885830074,6302476880, 46077527307,345590801495,2655466079629, 20880388012659,167861200630015,1378589193074514, 11558511053625488] |