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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 9 |
| 4 | 29 |
| 5 | 103 |
| 6 | 367 |
| 7 | 1337 |
| 8 | 5023 |
| 9 | 18933 |
| 10 | 72019 |
| 11 | 277595 |
| 12 | 1072317 |
| 13 | 4161419 |
| 14 | 16257277 |
| 15 | 63604357 |
| 16 | 249494725 |
| 17 | 982307399 |
| 18 | 3871371275 |
| 19 | 15281854703 |
| 20 | 60457884995 |
| 21 | 239348796175 |
| 22 | 948543450125 |
| 23 | 3764377613819 |
| 24 | 14946670066195 |
| 25 | 59387715592641 |
| 26 | 236183780014071 |
| 27 | 939637420512623 |
| 28 | 3740066423029775 |
[1,1,3,9,29,103,367,1337,5023,18933,72019,277595, 1072317,4161419,16257277,63604357,249494725, 982307399,3871371275,15281854703,60457884995, 239348796175,948543450125,3764377613819, 14946670066195,59387715592641,236183780014071, 939637420512623,3740066423029775] |