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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 10 |
| 4 | 42 |
| 5 | 210 |
| 6 | 1263 |
| 7 | 8845 |
| 8 | 70763 |
| 9 | 636874 |
| 10 | 6368742 |
| 11 | 70056165 |
| 12 | 840673988 |
| 13 | 10928761854 |
| 14 | 153002665956 |
| 15 | 2295039989346 |
| 16 | 36720639829536 |
| 17 | 624250877102116 |
| 18 | 11236515787838090 |
| 19 | 213493799968923719 |
| 20 | 4269875999378474390 |
[1,3,10,42,210,1263,8845,70763,636874,6368742, 70056165,840673988,10928761854,153002665956, 2295039989346,36720639829536,624250877102116, 11236515787838090,213493799968923719, 4269875999378474390] |