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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 1 |
| 5 | 5 |
| 6 | 15 |
| 7 | 35 |
| 8 | 70 |
| 9 | 126 |
| 10 | 210 |
| 11 | 330 |
| 12 | 495 |
| 13 | 715 |
| 14 | 1001 |
| 15 | 1365 |
| 16 | 1820 |
| 17 | 2380 |
| 18 | 3060 |
| 19 | 3876 |
| 20 | 4845 |
| 21 | 5985 |
| 22 | 7315 |
| 23 | 8855 |
| 24 | 10626 |
| 25 | 12650 |
| 26 | 14950 |
| 27 | 17550 |
| 28 | 20475 |
| 29 | 23751 |
| 30 | 27405 |
| 31 | 31465 |
| 32 | 35960 |
| 33 | 40920 |
| 34 | 46376 |
| 35 | 52360 |
| 36 | 58905 |
| 37 | 66045 |
| 38 | 73815 |
| 39 | 82251 |
| 40 | 91390 |
| 41 | 101270 |
| 42 | 111930 |
| 43 | 123410 |
[0,0,0,0,1,5,15,35,70,126,210,330,495,715,1001, 1365,1820,2380,3060,3876,4845,5985,7315,8855, 10626,12650,14950,17550,20475,23751,27405,31465, 35960,40920,46376,52360,58905,66045,73815,82251, 91390,101270,111930,123410] |