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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 8 |
| 4 | 39 |
| 5 | 214 |
| 6 | 1268 |
| 7 | 7949 |
| 8 | 51901 |
| 9 | 349703 |
| 10 | 2415348 |
| 11 | 17020341 |
| 12 | 121939535 |
| 13 | 885841162 |
| 14 | 6511874216 |
| 15 | 48359860685 |
| 16 | 362343773669 |
| 17 | 2736184763500 |
| 18 | 20805175635077 |
| 19 | 159174733727167 |
| 20 | 1224557214545788 |
| 21 | 9467861087020239 |
| 22 | 73534456468877012 |
| 23 | 573484090227222260 |
[1,2,8,39,214,1268,7949,51901,349703,2415348, 17020341,121939535,885841162,6511874216, 48359860685,362343773669,2736184763500, 20805175635077,159174733727167,1224557214545788, 9467861087020239,73534456468877012, 573484090227222260] |