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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 9 |
| 4 | 38 |
| 5 | 215 |
| 6 | 1384 |
| 7 | 10409 |
| 8 | 86946 |
| 9 | 825075 |
| 10 | 8541998 |
| 11 | 97590779 |
| 12 | 1205343952 |
| 13 | 16148472977 |
| 14 | 231416203212 |
| 15 | 3560209750005 |
| 16 | 58104163643054 |
| 17 | 1008693571819919 |
| 18 | 18477578835352366 |
| 19 | 357476371577422955 |
| 20 | 7258865626801695048 |
| 21 | 154893910336866444009 |
| 22 | 3454112338490001478772 |
[1,2,9,38,215,1384,10409,86946,825075,8541998, 97590779,1205343952,16148472977,231416203212, 3560209750005,58104163643054,1008693571819919, 18477578835352366,357476371577422955, 7258865626801695048,154893910336866444009, 3454112338490001478772] |