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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 3 |
| 5 | 4 |
| 6 | 6 |
| 7 | 10 |
| 8 | 15 |
| 9 | 21 |
| 10 | 35 |
| 11 | 56 |
| 12 | 84 |
| 13 | 126 |
| 14 | 210 |
| 15 | 330 |
| 16 | 495 |
| 17 | 792 |
| 18 | 1287 |
| 19 | 2002 |
| 20 | 3003 |
| 21 | 5005 |
| 22 | 8008 |
| 23 | 12376 |
| 24 | 19448 |
| 25 | 31824 |
| 26 | 50388 |
| 27 | 77520 |
| 28 | 125970 |
| 29 | 203490 |
| 30 | 319770 |
| 31 | 497420 |
| 32 | 817190 |
| 33 | 1307504 |
| 34 | 2042975 |
| 35 | 3268760 |
| 36 | 5311735 |
| 37 | 8436285 |
| 38 | 13123110 |
| 39 | 21474180 |
| 40 | 34597290 |
[1,1,1,2,3,4,6,10,15,21,35,56,84,126,210,330,495, 792,1287,2002,3003,5005,8008,12376,19448,31824, 50388,77520,125970,203490,319770,497420,817190, 1307504,2042975,3268760,5311735,8436285,13123110, 21474180,34597290] |