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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 5 |
| 4 | 14 |
| 5 | 42 |
| 6 | 66 |
| 7 | 429 |
| 8 | 1430 |
| 9 | 4862 |
| 10 | 8398 |
| 11 | 58786 |
| 12 | 104006 |
| 13 | 74290 |
| 14 | 222870 |
| 15 | 3231615 |
| 16 | 11785890 |
| 17 | 129644790 |
| 18 | 47763870 |
| 19 | 1767263190 |
| 20 | 3282060210 |
| 21 | 12233133510 |
| 22 | 22870640910 |
| 23 | 22870640910 |
| 24 | 214984024554 |
| 25 | 115760628606 |
| 26 | 655976895434 |
| 27 | 34766775458002 |
| 28 | 65936987937590 |
[1,1,2,5,14,42,66,429,1430,4862,8398,58786,104006, 74290,222870,3231615,11785890,129644790,47763870, 1767263190,3282060210,12233133510,22870640910, 22870640910,214984024554,115760628606, 655976895434,34766775458002,65936987937590] |