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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 1 |
| 6 | 1 |
| 7 | 2 |
| 8 | 3 |
| 9 | 5 |
| 10 | 7 |
| 11 | 16 |
| 12 | 27 |
| 13 | 69 |
| 14 | 151 |
| 15 | 481 |
| 16 | 1224 |
| 17 | 4362 |
| 18 | 12863 |
| 19 | 54770 |
| 20 | 198381 |
| 21 | 1006602 |
| 22 | 4307827 |
| 23 | 25870297 |
| 24 | 130523404 |
| 25 | 917353447 |
| 26 | 5499437681 |
| 27 | 46147817424 |
| 28 | 329292463469 |
| 29 | 3264965678695 |
| 30 | 27531225103405 |
[1,1,1,1,1,1,2,3,5,7,16,27,69,151,481,1224,4362, 12863,54770,198381,1006602,4307827,25870297, 130523404,917353447,5499437681,46147817424, 329292463469,3264965678695,27531225103405] |