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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 10 |
| 4 | 35 |
| 5 | 126 |
| 6 | 462 |
| 7 | 1716 |
| 8 | 6435 |
| 9 | 24310 |
| 10 | 92368 |
| 11 | 352595 |
| 12 | 1351142 |
| 13 | 5194385 |
| 14 | 20024980 |
| 15 | 77384340 |
| 16 | 299671971 |
| 17 | 1162635441 |
| 18 | 4518099300 |
| 19 | 17583582225 |
| 20 | 68522664400 |
| 21 | 267350823015 |
| 22 | 1044243559263 |
| 23 | 4082760176300 |
| 24 | 15977236602150 |
| 25 | 62576817828876 |
| 26 | 245279492151021 |
[1,3,10,35,126,462,1716,6435,24310,92368,352595, 1351142,5194385,20024980,77384340,299671971, 1162635441,4518099300,17583582225,68522664400, 267350823015,1044243559263,4082760176300, 15977236602150,62576817828876,245279492151021] |