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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 3 |
| 4 | 6 |
| 5 | 15 |
| 6 | 29 |
| 7 | 63 |
| 8 | 160 |
| 9 | 333 |
| 10 | 749 |
| 11 | 1914 |
| 12 | 4135 |
| 13 | 9490 |
| 14 | 24335 |
| 15 | 53791 |
| 16 | 125104 |
| 17 | 321521 |
| 18 | 721887 |
| 19 | 1694914 |
| 20 | 4362855 |
| 21 | 9907851 |
| 22 | 23429158 |
| 23 | 60379623 |
| 24 | 138320021 |
| 25 | 328917615 |
| 26 | 848432824 |
| 27 | 1957091277 |
| 28 | 4674847097 |
| 29 | 12067450014 |
| 30 | 27992976565 |
[1,1,2,3,6,15,29,63,160,333,749,1914,4135,9490, 24335,53791,125104,321521,721887,1694914,4362855, 9907851,23429158,60379623,138320021,328917615, 848432824,1957091277,4674847097,12067450014, 27992976565] |