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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 5 |
| 4 | 14 |
| 5 | 55 |
| 6 | 287 |
| 7 | 2165 |
| 8 | 21835 |
| 9 | 252726 |
| 10 | 3096256 |
| 11 | 38732624 |
| 12 | 488632335 |
| 13 | 6180876159 |
| 14 | 78236666009 |
| 15 | 990197916540 |
| 16 | 12529967750879 |
| 17 | 158558090021956 |
| 18 | 2007064954804659 |
[1,2,5,14,55,287,2165,21835,252726,3096256, 38732624,488632335,6180876159,78236666009, 990197916540,12529967750879,158558090021956, 2007064954804659] |