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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 3 |
| 4 | 6 |
| 5 | 10 |
| 6 | 20 |
| 7 | 35 |
| 8 | 70 |
| 9 | 126 |
| 10 | 252 |
| 11 | 462 |
| 12 | 924 |
| 13 | 1716 |
| 14 | 429 |
| 15 | 6435 |
| 16 | 12870 |
| 17 | 24310 |
| 18 | 48620 |
| 19 | 92378 |
| 20 | 184756 |
| 21 | 352716 |
| 22 | 88179 |
| 23 | 1352078 |
| 24 | 2704156 |
| 25 | 5200300 |
| 26 | 1300075 |
| 27 | 742900 |
| 28 | 185725 |
| 29 | 9694845 |
| 30 | 155117520 |
| 31 | 300540195 |
| 32 | 601080390 |
| 33 | 43214930 |
| 34 | 86429860 |
[1,2,3,6,10,20,35,70,126,252,462,924,1716,429, 6435,12870,24310,48620,92378,184756,352716,88179, 1352078,2704156,5200300,1300075,742900,185725, 9694845,155117520,300540195,601080390,43214930, 86429860] |